kvm_main.c 93.1 KB
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Avi Kivity 已提交
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/*
 * Kernel-based Virtual Machine driver for Linux
 *
 * This module enables machines with Intel VT-x extensions to run virtual
 * machines without emulation or binary translation.
 *
 * Copyright (C) 2006 Qumranet, Inc.
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 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
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 *
 * Authors:
 *   Avi Kivity   <avi@qumranet.com>
 *   Yaniv Kamay  <yaniv@qumranet.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2.  See
 * the COPYING file in the top-level directory.
 *
 */

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#include <kvm/iodev.h>
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#include <linux/kvm_host.h>
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#include <linux/kvm.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/percpu.h>
#include <linux/mm.h>
#include <linux/miscdevice.h>
#include <linux/vmalloc.h>
#include <linux/reboot.h>
#include <linux/debugfs.h>
#include <linux/highmem.h>
#include <linux/file.h>
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#include <linux/syscore_ops.h>
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#include <linux/cpu.h>
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#include <linux/sched.h>
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#include <linux/cpumask.h>
#include <linux/smp.h>
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#include <linux/anon_inodes.h>
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#include <linux/profile.h>
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#include <linux/kvm_para.h>
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#include <linux/pagemap.h>
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#include <linux/mman.h>
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#include <linux/swap.h>
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#include <linux/bitops.h>
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#include <linux/spinlock.h>
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#include <linux/compat.h>
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#include <linux/srcu.h>
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#include <linux/hugetlb.h>
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#include <linux/slab.h>
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#include <linux/sort.h>
#include <linux/bsearch.h>
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#include <asm/processor.h>
#include <asm/io.h>
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#include <asm/ioctl.h>
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#include <asm/uaccess.h>
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#include <asm/pgtable.h>
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#include "coalesced_mmio.h"
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#include "async_pf.h"
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#include "vfio.h"
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#define CREATE_TRACE_POINTS
#include <trace/events/kvm.h>

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/* Worst case buffer size needed for holding an integer. */
#define ITOA_MAX_LEN 12

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MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");

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/* Architectures should define their poll value according to the halt latency */
static unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
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module_param(halt_poll_ns, uint, S_IRUGO | S_IWUSR);

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/* Default doubles per-vcpu halt_poll_ns. */
static unsigned int halt_poll_ns_grow = 2;
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module_param(halt_poll_ns_grow, uint, S_IRUGO | S_IWUSR);
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/* Default resets per-vcpu halt_poll_ns . */
static unsigned int halt_poll_ns_shrink;
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module_param(halt_poll_ns_shrink, uint, S_IRUGO | S_IWUSR);
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/*
 * Ordering of locks:
 *
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 *	kvm->lock --> kvm->slots_lock --> kvm->irq_lock
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 */

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DEFINE_SPINLOCK(kvm_lock);
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static DEFINE_RAW_SPINLOCK(kvm_count_lock);
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LIST_HEAD(vm_list);
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static cpumask_var_t cpus_hardware_enabled;
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static int kvm_usage_count;
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static atomic_t hardware_enable_failed;
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struct kmem_cache *kvm_vcpu_cache;
EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
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static __read_mostly struct preempt_ops kvm_preempt_ops;

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struct dentry *kvm_debugfs_dir;
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EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
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static int kvm_debugfs_num_entries;
static const struct file_operations *stat_fops_per_vm[];

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static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
			   unsigned long arg);
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#ifdef CONFIG_KVM_COMPAT
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static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
				  unsigned long arg);
#endif
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static int hardware_enable_all(void);
static void hardware_disable_all(void);
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static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
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static void kvm_release_pfn_dirty(kvm_pfn_t pfn);
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static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
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__visible bool kvm_rebooting;
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EXPORT_SYMBOL_GPL(kvm_rebooting);
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static bool largepages_enabled = true;

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bool kvm_is_reserved_pfn(kvm_pfn_t pfn)
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{
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	if (pfn_valid(pfn))
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		return PageReserved(pfn_to_page(pfn));
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	return true;
}

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/*
 * Switches to specified vcpu, until a matching vcpu_put()
 */
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int vcpu_load(struct kvm_vcpu *vcpu)
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{
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	int cpu;

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	if (mutex_lock_killable(&vcpu->mutex))
		return -EINTR;
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	cpu = get_cpu();
	preempt_notifier_register(&vcpu->preempt_notifier);
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	kvm_arch_vcpu_load(vcpu, cpu);
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	put_cpu();
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	return 0;
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}
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EXPORT_SYMBOL_GPL(vcpu_load);
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void vcpu_put(struct kvm_vcpu *vcpu)
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{
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	preempt_disable();
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	kvm_arch_vcpu_put(vcpu);
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	preempt_notifier_unregister(&vcpu->preempt_notifier);
	preempt_enable();
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	mutex_unlock(&vcpu->mutex);
}
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EXPORT_SYMBOL_GPL(vcpu_put);
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static void ack_flush(void *_completed)
{
}

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bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
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{
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	int i, cpu, me;
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	cpumask_var_t cpus;
	bool called = true;
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	struct kvm_vcpu *vcpu;

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	zalloc_cpumask_var(&cpus, GFP_ATOMIC);
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	me = get_cpu();
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	kvm_for_each_vcpu(i, vcpu, kvm) {
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		kvm_make_request(req, vcpu);
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		cpu = vcpu->cpu;
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		/* Set ->requests bit before we read ->mode. */
		smp_mb__after_atomic();
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		if (cpus != NULL && cpu != -1 && cpu != me &&
		      kvm_vcpu_exiting_guest_mode(vcpu) != OUTSIDE_GUEST_MODE)
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			cpumask_set_cpu(cpu, cpus);
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	}
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	if (unlikely(cpus == NULL))
		smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
	else if (!cpumask_empty(cpus))
		smp_call_function_many(cpus, ack_flush, NULL, 1);
	else
		called = false;
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	put_cpu();
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	free_cpumask_var(cpus);
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	return called;
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}

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#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
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void kvm_flush_remote_tlbs(struct kvm *kvm)
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{
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	/*
	 * Read tlbs_dirty before setting KVM_REQ_TLB_FLUSH in
	 * kvm_make_all_cpus_request.
	 */
	long dirty_count = smp_load_acquire(&kvm->tlbs_dirty);

	/*
	 * We want to publish modifications to the page tables before reading
	 * mode. Pairs with a memory barrier in arch-specific code.
	 * - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
	 * and smp_mb in walk_shadow_page_lockless_begin/end.
	 * - powerpc: smp_mb in kvmppc_prepare_to_enter.
	 *
	 * There is already an smp_mb__after_atomic() before
	 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
	 * barrier here.
	 */
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	if (kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
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		++kvm->stat.remote_tlb_flush;
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	cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
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}
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EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
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#endif
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void kvm_reload_remote_mmus(struct kvm *kvm)
{
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	kvm_make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
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}
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int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
{
	struct page *page;
	int r;

	mutex_init(&vcpu->mutex);
	vcpu->cpu = -1;
	vcpu->kvm = kvm;
	vcpu->vcpu_id = id;
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	vcpu->pid = NULL;
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	init_swait_queue_head(&vcpu->wq);
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	kvm_async_pf_vcpu_init(vcpu);
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	vcpu->pre_pcpu = -1;
	INIT_LIST_HEAD(&vcpu->blocked_vcpu_list);

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	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
	if (!page) {
		r = -ENOMEM;
		goto fail;
	}
	vcpu->run = page_address(page);

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	kvm_vcpu_set_in_spin_loop(vcpu, false);
	kvm_vcpu_set_dy_eligible(vcpu, false);
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	vcpu->preempted = false;
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	r = kvm_arch_vcpu_init(vcpu);
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	if (r < 0)
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		goto fail_free_run;
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	return 0;

fail_free_run:
	free_page((unsigned long)vcpu->run);
fail:
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	return r;
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}
EXPORT_SYMBOL_GPL(kvm_vcpu_init);

void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
{
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	put_pid(vcpu->pid);
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	kvm_arch_vcpu_uninit(vcpu);
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	free_page((unsigned long)vcpu->run);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);

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#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
{
	return container_of(mn, struct kvm, mmu_notifier);
}

static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
					     struct mm_struct *mm,
					     unsigned long address)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int need_tlb_flush, idx;
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	/*
	 * When ->invalidate_page runs, the linux pte has been zapped
	 * already but the page is still allocated until
	 * ->invalidate_page returns. So if we increase the sequence
	 * here the kvm page fault will notice if the spte can't be
	 * established because the page is going to be freed. If
	 * instead the kvm page fault establishes the spte before
	 * ->invalidate_page runs, kvm_unmap_hva will release it
	 * before returning.
	 *
	 * The sequence increase only need to be seen at spin_unlock
	 * time, and not at spin_lock time.
	 *
	 * Increasing the sequence after the spin_unlock would be
	 * unsafe because the kvm page fault could then establish the
	 * pte after kvm_unmap_hva returned, without noticing the page
	 * is going to be freed.
	 */
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	idx = srcu_read_lock(&kvm->srcu);
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	spin_lock(&kvm->mmu_lock);
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	kvm->mmu_notifier_seq++;
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	need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty;
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	/* we've to flush the tlb before the pages can be freed */
	if (need_tlb_flush)
		kvm_flush_remote_tlbs(kvm);

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	spin_unlock(&kvm->mmu_lock);
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	kvm_arch_mmu_notifier_invalidate_page(kvm, address);

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	srcu_read_unlock(&kvm->srcu, idx);
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}

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static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
					struct mm_struct *mm,
					unsigned long address,
					pte_t pte)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int idx;
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	idx = srcu_read_lock(&kvm->srcu);
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	spin_lock(&kvm->mmu_lock);
	kvm->mmu_notifier_seq++;
	kvm_set_spte_hva(kvm, address, pte);
	spin_unlock(&kvm->mmu_lock);
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	srcu_read_unlock(&kvm->srcu, idx);
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}

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static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
						    struct mm_struct *mm,
						    unsigned long start,
						    unsigned long end)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int need_tlb_flush = 0, idx;
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	idx = srcu_read_lock(&kvm->srcu);
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	spin_lock(&kvm->mmu_lock);
	/*
	 * The count increase must become visible at unlock time as no
	 * spte can be established without taking the mmu_lock and
	 * count is also read inside the mmu_lock critical section.
	 */
	kvm->mmu_notifier_count++;
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	need_tlb_flush = kvm_unmap_hva_range(kvm, start, end);
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	need_tlb_flush |= kvm->tlbs_dirty;
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	/* we've to flush the tlb before the pages can be freed */
	if (need_tlb_flush)
		kvm_flush_remote_tlbs(kvm);
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	spin_unlock(&kvm->mmu_lock);
	srcu_read_unlock(&kvm->srcu, idx);
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}

static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
						  struct mm_struct *mm,
						  unsigned long start,
						  unsigned long end)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);

	spin_lock(&kvm->mmu_lock);
	/*
	 * This sequence increase will notify the kvm page fault that
	 * the page that is going to be mapped in the spte could have
	 * been freed.
	 */
	kvm->mmu_notifier_seq++;
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	smp_wmb();
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	/*
	 * The above sequence increase must be visible before the
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	 * below count decrease, which is ensured by the smp_wmb above
	 * in conjunction with the smp_rmb in mmu_notifier_retry().
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	 */
	kvm->mmu_notifier_count--;
	spin_unlock(&kvm->mmu_lock);

	BUG_ON(kvm->mmu_notifier_count < 0);
}

static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
					      struct mm_struct *mm,
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					      unsigned long start,
					      unsigned long end)
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{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int young, idx;
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	idx = srcu_read_lock(&kvm->srcu);
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	spin_lock(&kvm->mmu_lock);

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	young = kvm_age_hva(kvm, start, end);
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	if (young)
		kvm_flush_remote_tlbs(kvm);

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	spin_unlock(&kvm->mmu_lock);
	srcu_read_unlock(&kvm->srcu, idx);

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	return young;
}

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static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
					struct mm_struct *mm,
					unsigned long start,
					unsigned long end)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
	int young, idx;

	idx = srcu_read_lock(&kvm->srcu);
	spin_lock(&kvm->mmu_lock);
	/*
	 * Even though we do not flush TLB, this will still adversely
	 * affect performance on pre-Haswell Intel EPT, where there is
	 * no EPT Access Bit to clear so that we have to tear down EPT
	 * tables instead. If we find this unacceptable, we can always
	 * add a parameter to kvm_age_hva so that it effectively doesn't
	 * do anything on clear_young.
	 *
	 * Also note that currently we never issue secondary TLB flushes
	 * from clear_young, leaving this job up to the regular system
	 * cadence. If we find this inaccurate, we might come up with a
	 * more sophisticated heuristic later.
	 */
	young = kvm_age_hva(kvm, start, end);
	spin_unlock(&kvm->mmu_lock);
	srcu_read_unlock(&kvm->srcu, idx);

	return young;
}

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static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
				       struct mm_struct *mm,
				       unsigned long address)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
	int young, idx;

	idx = srcu_read_lock(&kvm->srcu);
	spin_lock(&kvm->mmu_lock);
	young = kvm_test_age_hva(kvm, address);
	spin_unlock(&kvm->mmu_lock);
	srcu_read_unlock(&kvm->srcu, idx);

	return young;
}

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static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
				     struct mm_struct *mm)
{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int idx;

	idx = srcu_read_lock(&kvm->srcu);
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	kvm_arch_flush_shadow_all(kvm);
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	srcu_read_unlock(&kvm->srcu, idx);
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}

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static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
	.invalidate_page	= kvm_mmu_notifier_invalidate_page,
	.invalidate_range_start	= kvm_mmu_notifier_invalidate_range_start,
	.invalidate_range_end	= kvm_mmu_notifier_invalidate_range_end,
	.clear_flush_young	= kvm_mmu_notifier_clear_flush_young,
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	.clear_young		= kvm_mmu_notifier_clear_young,
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	.test_young		= kvm_mmu_notifier_test_young,
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	.change_pte		= kvm_mmu_notifier_change_pte,
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	.release		= kvm_mmu_notifier_release,
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};
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static int kvm_init_mmu_notifier(struct kvm *kvm)
{
	kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
	return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
}

#else  /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */

static int kvm_init_mmu_notifier(struct kvm *kvm)
{
	return 0;
}

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#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */

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static struct kvm_memslots *kvm_alloc_memslots(void)
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{
	int i;
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	struct kvm_memslots *slots;
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	slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
	if (!slots)
		return NULL;

	/*
	 * Init kvm generation close to the maximum to easily test the
	 * code of handling generation number wrap-around.
	 */
	slots->generation = -150;
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	for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
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		slots->id_to_index[i] = slots->memslots[i].id = i;
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	return slots;
}

static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
{
	if (!memslot->dirty_bitmap)
		return;

	kvfree(memslot->dirty_bitmap);
	memslot->dirty_bitmap = NULL;
}

/*
 * Free any memory in @free but not in @dont.
 */
static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
			      struct kvm_memory_slot *dont)
{
	if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
		kvm_destroy_dirty_bitmap(free);

	kvm_arch_free_memslot(kvm, free, dont);

	free->npages = 0;
}

static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
{
	struct kvm_memory_slot *memslot;

	if (!slots)
		return;

	kvm_for_each_memslot(memslot, slots)
		kvm_free_memslot(kvm, memslot, NULL);

	kvfree(slots);
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}

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static void kvm_destroy_vm_debugfs(struct kvm *kvm)
{
	int i;

	if (!kvm->debugfs_dentry)
		return;

	debugfs_remove_recursive(kvm->debugfs_dentry);

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	if (kvm->debugfs_stat_data) {
		for (i = 0; i < kvm_debugfs_num_entries; i++)
			kfree(kvm->debugfs_stat_data[i]);
		kfree(kvm->debugfs_stat_data);
	}
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}

static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
{
	char dir_name[ITOA_MAX_LEN * 2];
	struct kvm_stat_data *stat_data;
	struct kvm_stats_debugfs_item *p;

	if (!debugfs_initialized())
		return 0;

	snprintf(dir_name, sizeof(dir_name), "%d-%d", task_pid_nr(current), fd);
	kvm->debugfs_dentry = debugfs_create_dir(dir_name,
						 kvm_debugfs_dir);
	if (!kvm->debugfs_dentry)
		return -ENOMEM;

	kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
					 sizeof(*kvm->debugfs_stat_data),
					 GFP_KERNEL);
	if (!kvm->debugfs_stat_data)
		return -ENOMEM;

	for (p = debugfs_entries; p->name; p++) {
		stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL);
		if (!stat_data)
			return -ENOMEM;

		stat_data->kvm = kvm;
		stat_data->offset = p->offset;
		kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
598
		if (!debugfs_create_file(p->name, 0644,
599 600 601 602 603 604 605 606
					 kvm->debugfs_dentry,
					 stat_data,
					 stat_fops_per_vm[p->kind]))
			return -ENOMEM;
	}
	return 0;
}

607
static struct kvm *kvm_create_vm(unsigned long type)
A
Avi Kivity 已提交
608
{
609 610
	int r, i;
	struct kvm *kvm = kvm_arch_alloc_vm();
A
Avi Kivity 已提交
611

612 613 614
	if (!kvm)
		return ERR_PTR(-ENOMEM);

615 616 617 618 619 620 621 622 623 624
	spin_lock_init(&kvm->mmu_lock);
	atomic_inc(&current->mm->mm_count);
	kvm->mm = current->mm;
	kvm_eventfd_init(kvm);
	mutex_init(&kvm->lock);
	mutex_init(&kvm->irq_lock);
	mutex_init(&kvm->slots_lock);
	atomic_set(&kvm->users_count, 1);
	INIT_LIST_HEAD(&kvm->devices);

625
	r = kvm_arch_init_vm(kvm, type);
626
	if (r)
627
		goto out_err_no_disable;
628 629 630

	r = hardware_enable_all();
	if (r)
631
		goto out_err_no_disable;
632

633
#ifdef CONFIG_HAVE_KVM_IRQFD
634
	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
635
#endif
A
Avi Kivity 已提交
636

637 638
	BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);

639
	r = -ENOMEM;
640 641 642 643 644
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
		kvm->memslots[i] = kvm_alloc_memslots();
		if (!kvm->memslots[i])
			goto out_err_no_srcu;
	}
645

646
	if (init_srcu_struct(&kvm->srcu))
647 648 649
		goto out_err_no_srcu;
	if (init_srcu_struct(&kvm->irq_srcu))
		goto out_err_no_irq_srcu;
M
Marcelo Tosatti 已提交
650 651 652
	for (i = 0; i < KVM_NR_BUSES; i++) {
		kvm->buses[i] = kzalloc(sizeof(struct kvm_io_bus),
					GFP_KERNEL);
653
		if (!kvm->buses[i])
M
Marcelo Tosatti 已提交
654 655
			goto out_err;
	}
656

657 658 659 660
	r = kvm_init_mmu_notifier(kvm);
	if (r)
		goto out_err;

661
	spin_lock(&kvm_lock);
662
	list_add(&kvm->vm_list, &vm_list);
663
	spin_unlock(&kvm_lock);
664

665 666
	preempt_notifier_inc();

667
	return kvm;
668 669

out_err:
670 671
	cleanup_srcu_struct(&kvm->irq_srcu);
out_err_no_irq_srcu:
672
	cleanup_srcu_struct(&kvm->srcu);
673
out_err_no_srcu:
674
	hardware_disable_all();
675
out_err_no_disable:
M
Marcelo Tosatti 已提交
676 677
	for (i = 0; i < KVM_NR_BUSES; i++)
		kfree(kvm->buses[i]);
678 679
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
		kvm_free_memslots(kvm, kvm->memslots[i]);
680
	kvm_arch_free_vm(kvm);
681
	mmdrop(current->mm);
682
	return ERR_PTR(r);
683 684
}

685 686 687 688
/*
 * Avoid using vmalloc for a small buffer.
 * Should not be used when the size is statically known.
 */
689
void *kvm_kvzalloc(unsigned long size)
690 691 692 693 694 695 696
{
	if (size > PAGE_SIZE)
		return vzalloc(size);
	else
		return kzalloc(size, GFP_KERNEL);
}

697 698
static void kvm_destroy_devices(struct kvm *kvm)
{
G
Geliang Tang 已提交
699
	struct kvm_device *dev, *tmp;
700

701 702 703 704 705
	/*
	 * We do not need to take the kvm->lock here, because nobody else
	 * has a reference to the struct kvm at this point and therefore
	 * cannot access the devices list anyhow.
	 */
G
Geliang Tang 已提交
706 707
	list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
		list_del(&dev->vm_node);
708 709 710 711
		dev->ops->destroy(dev);
	}
}

712 713
static void kvm_destroy_vm(struct kvm *kvm)
{
M
Marcelo Tosatti 已提交
714
	int i;
715 716
	struct mm_struct *mm = kvm->mm;

717
	kvm_destroy_vm_debugfs(kvm);
718
	kvm_arch_sync_events(kvm);
719
	spin_lock(&kvm_lock);
720
	list_del(&kvm->vm_list);
721
	spin_unlock(&kvm_lock);
722
	kvm_free_irq_routing(kvm);
M
Marcelo Tosatti 已提交
723 724
	for (i = 0; i < KVM_NR_BUSES; i++)
		kvm_io_bus_destroy(kvm->buses[i]);
725
	kvm_coalesced_mmio_free(kvm);
726 727
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
728
#else
729
	kvm_arch_flush_shadow_all(kvm);
730
#endif
731
	kvm_arch_destroy_vm(kvm);
732
	kvm_destroy_devices(kvm);
733 734
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
		kvm_free_memslots(kvm, kvm->memslots[i]);
735
	cleanup_srcu_struct(&kvm->irq_srcu);
736 737
	cleanup_srcu_struct(&kvm->srcu);
	kvm_arch_free_vm(kvm);
738
	preempt_notifier_dec();
739
	hardware_disable_all();
740
	mmdrop(mm);
741 742
}

I
Izik Eidus 已提交
743 744 745 746 747 748 749 750 751 752 753 754 755 756
void kvm_get_kvm(struct kvm *kvm)
{
	atomic_inc(&kvm->users_count);
}
EXPORT_SYMBOL_GPL(kvm_get_kvm);

void kvm_put_kvm(struct kvm *kvm)
{
	if (atomic_dec_and_test(&kvm->users_count))
		kvm_destroy_vm(kvm);
}
EXPORT_SYMBOL_GPL(kvm_put_kvm);


757 758 759 760
static int kvm_vm_release(struct inode *inode, struct file *filp)
{
	struct kvm *kvm = filp->private_data;

G
Gregory Haskins 已提交
761 762
	kvm_irqfd_release(kvm);

I
Izik Eidus 已提交
763
	kvm_put_kvm(kvm);
A
Avi Kivity 已提交
764 765 766
	return 0;
}

767 768
/*
 * Allocation size is twice as large as the actual dirty bitmap size.
769
 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
770
 */
771 772
static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
{
773
	unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
774

775
	memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes);
776 777 778 779 780 781
	if (!memslot->dirty_bitmap)
		return -ENOMEM;

	return 0;
}

782
/*
783 784 785 786
 * Insert memslot and re-sort memslots based on their GFN,
 * so binary search could be used to lookup GFN.
 * Sorting algorithm takes advantage of having initially
 * sorted array and known changed memslot position.
787
 */
788 789
static void update_memslots(struct kvm_memslots *slots,
			    struct kvm_memory_slot *new)
790
{
791 792
	int id = new->id;
	int i = slots->id_to_index[id];
793
	struct kvm_memory_slot *mslots = slots->memslots;
794

795
	WARN_ON(mslots[i].id != id);
796
	if (!new->npages) {
797
		WARN_ON(!mslots[i].npages);
798 799 800 801 802 803
		if (mslots[i].npages)
			slots->used_slots--;
	} else {
		if (!mslots[i].npages)
			slots->used_slots++;
	}
804

805
	while (i < KVM_MEM_SLOTS_NUM - 1 &&
806 807 808
	       new->base_gfn <= mslots[i + 1].base_gfn) {
		if (!mslots[i + 1].npages)
			break;
809 810 811 812
		mslots[i] = mslots[i + 1];
		slots->id_to_index[mslots[i].id] = i;
		i++;
	}
813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829

	/*
	 * The ">=" is needed when creating a slot with base_gfn == 0,
	 * so that it moves before all those with base_gfn == npages == 0.
	 *
	 * On the other hand, if new->npages is zero, the above loop has
	 * already left i pointing to the beginning of the empty part of
	 * mslots, and the ">=" would move the hole backwards in this
	 * case---which is wrong.  So skip the loop when deleting a slot.
	 */
	if (new->npages) {
		while (i > 0 &&
		       new->base_gfn >= mslots[i - 1].base_gfn) {
			mslots[i] = mslots[i - 1];
			slots->id_to_index[mslots[i].id] = i;
			i--;
		}
830 831
	} else
		WARN_ON_ONCE(i != slots->used_slots);
832

833 834
	mslots[i] = *new;
	slots->id_to_index[mslots[i].id] = i;
835 836
}

837
static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
838
{
X
Xiao Guangrong 已提交
839 840
	u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;

841
#ifdef __KVM_HAVE_READONLY_MEM
X
Xiao Guangrong 已提交
842 843 844 845
	valid_flags |= KVM_MEM_READONLY;
#endif

	if (mem->flags & ~valid_flags)
846 847 848 849 850
		return -EINVAL;

	return 0;
}

851
static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
852
		int as_id, struct kvm_memslots *slots)
853
{
854
	struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
855

856 857 858 859 860 861 862
	/*
	 * Set the low bit in the generation, which disables SPTE caching
	 * until the end of synchronize_srcu_expedited.
	 */
	WARN_ON(old_memslots->generation & 1);
	slots->generation = old_memslots->generation + 1;

863
	rcu_assign_pointer(kvm->memslots[as_id], slots);
864
	synchronize_srcu_expedited(&kvm->srcu);
865

866 867 868 869 870 871 872
	/*
	 * Increment the new memslot generation a second time. This prevents
	 * vm exits that race with memslot updates from caching a memslot
	 * generation that will (potentially) be valid forever.
	 */
	slots->generation++;

873
	kvm_arch_memslots_updated(kvm, slots);
874 875

	return old_memslots;
876 877
}

A
Avi Kivity 已提交
878 879 880 881 882
/*
 * Allocate some memory and give it an address in the guest physical address
 * space.
 *
 * Discontiguous memory is allowed, mostly for framebuffers.
883
 *
884
 * Must be called holding kvm->slots_lock for write.
A
Avi Kivity 已提交
885
 */
886
int __kvm_set_memory_region(struct kvm *kvm,
887
			    const struct kvm_userspace_memory_region *mem)
A
Avi Kivity 已提交
888
{
889
	int r;
A
Avi Kivity 已提交
890
	gfn_t base_gfn;
891
	unsigned long npages;
892
	struct kvm_memory_slot *slot;
A
Avi Kivity 已提交
893
	struct kvm_memory_slot old, new;
894
	struct kvm_memslots *slots = NULL, *old_memslots;
895
	int as_id, id;
896
	enum kvm_mr_change change;
A
Avi Kivity 已提交
897

898 899 900 901
	r = check_memory_region_flags(mem);
	if (r)
		goto out;

A
Avi Kivity 已提交
902
	r = -EINVAL;
903 904 905
	as_id = mem->slot >> 16;
	id = (u16)mem->slot;

A
Avi Kivity 已提交
906 907 908 909 910
	/* General sanity checks */
	if (mem->memory_size & (PAGE_SIZE - 1))
		goto out;
	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
		goto out;
911
	/* We can read the guest memory with __xxx_user() later on. */
912
	if ((id < KVM_USER_MEM_SLOTS) &&
913
	    ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
914 915 916
	     !access_ok(VERIFY_WRITE,
			(void __user *)(unsigned long)mem->userspace_addr,
			mem->memory_size)))
917
		goto out;
918
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
A
Avi Kivity 已提交
919 920 921 922
		goto out;
	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
		goto out;

923
	slot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
A
Avi Kivity 已提交
924 925 926
	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
	npages = mem->memory_size >> PAGE_SHIFT;

927 928 929
	if (npages > KVM_MEM_MAX_NR_PAGES)
		goto out;

930
	new = old = *slot;
A
Avi Kivity 已提交
931

932
	new.id = id;
A
Avi Kivity 已提交
933 934 935 936
	new.base_gfn = base_gfn;
	new.npages = npages;
	new.flags = mem->flags;

937 938 939 940 941
	if (npages) {
		if (!old.npages)
			change = KVM_MR_CREATE;
		else { /* Modify an existing slot. */
			if ((mem->userspace_addr != old.userspace_addr) ||
942 943
			    (npages != old.npages) ||
			    ((new.flags ^ old.flags) & KVM_MEM_READONLY))
944 945 946 947 948 949 950 951 952 953 954
				goto out;

			if (base_gfn != old.base_gfn)
				change = KVM_MR_MOVE;
			else if (new.flags != old.flags)
				change = KVM_MR_FLAGS_ONLY;
			else { /* Nothing to change. */
				r = 0;
				goto out;
			}
		}
955 956 957 958
	} else {
		if (!old.npages)
			goto out;

959
		change = KVM_MR_DELETE;
960 961 962
		new.base_gfn = 0;
		new.flags = 0;
	}
A
Avi Kivity 已提交
963

964
	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
965 966
		/* Check for overlaps */
		r = -EEXIST;
967
		kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) {
968
			if ((slot->id >= KVM_USER_MEM_SLOTS) ||
969
			    (slot->id == id))
970 971 972 973 974
				continue;
			if (!((base_gfn + npages <= slot->base_gfn) ||
			      (base_gfn >= slot->base_gfn + slot->npages)))
				goto out;
		}
A
Avi Kivity 已提交
975 976 977 978
	}

	/* Free page dirty bitmap if unneeded */
	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
A
Al Viro 已提交
979
		new.dirty_bitmap = NULL;
A
Avi Kivity 已提交
980 981

	r = -ENOMEM;
982
	if (change == KVM_MR_CREATE) {
983
		new.userspace_addr = mem->userspace_addr;
984

985
		if (kvm_arch_create_memslot(kvm, &new, npages))
986
			goto out_free;
A
Avi Kivity 已提交
987
	}
988

A
Avi Kivity 已提交
989 990
	/* Allocate page dirty bitmap if needed */
	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
991
		if (kvm_create_dirty_bitmap(&new) < 0)
992
			goto out_free;
A
Avi Kivity 已提交
993 994
	}

995
	slots = kvm_kvzalloc(sizeof(struct kvm_memslots));
996 997
	if (!slots)
		goto out_free;
998
	memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));
999

1000
	if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
1001
		slot = id_to_memslot(slots, id);
1002 1003
		slot->flags |= KVM_MEMSLOT_INVALID;

1004
		old_memslots = install_new_memslots(kvm, as_id, slots);
1005

1006 1007
		/* slot was deleted or moved, clear iommu mapping */
		kvm_iommu_unmap_pages(kvm, &old);
1008 1009
		/* From this point no new shadow pages pointing to a deleted,
		 * or moved, memslot will be created.
1010 1011
		 *
		 * validation of sp->gfn happens in:
1012 1013
		 *	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
		 *	- kvm_is_visible_gfn (mmu_check_roots)
1014
		 */
1015
		kvm_arch_flush_shadow_memslot(kvm, slot);
1016 1017 1018 1019 1020 1021

		/*
		 * We can re-use the old_memslots from above, the only difference
		 * from the currently installed memslots is the invalid flag.  This
		 * will get overwritten by update_memslots anyway.
		 */
1022
		slots = old_memslots;
1023
	}
1024

1025
	r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
1026
	if (r)
1027
		goto out_slots;
1028

1029
	/* actual memory is freed via old in kvm_free_memslot below */
1030
	if (change == KVM_MR_DELETE) {
1031
		new.dirty_bitmap = NULL;
1032
		memset(&new.arch, 0, sizeof(new.arch));
1033 1034
	}

1035
	update_memslots(slots, &new);
1036
	old_memslots = install_new_memslots(kvm, as_id, slots);
1037

1038
	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
1039

1040
	kvm_free_memslot(kvm, &old, &new);
1041
	kvfree(old_memslots);
1042

1043 1044
	/*
	 * IOMMU mapping:  New slots need to be mapped.  Old slots need to be
1045 1046 1047 1048 1049 1050
	 * un-mapped and re-mapped if their base changes.  Since base change
	 * unmapping is handled above with slot deletion, mapping alone is
	 * needed here.  Anything else the iommu might care about for existing
	 * slots (size changes, userspace addr changes and read-only flag
	 * changes) is disallowed above, so any other attribute changes getting
	 * here can be skipped.
1051
	 */
1052 1053
	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
		r = kvm_iommu_map_pages(kvm, &new);
1054
		return r;
1055 1056
	}

A
Avi Kivity 已提交
1057 1058
	return 0;

1059
out_slots:
1060
	kvfree(slots);
1061
out_free:
1062
	kvm_free_memslot(kvm, &new, &old);
A
Avi Kivity 已提交
1063 1064
out:
	return r;
1065
}
1066 1067 1068
EXPORT_SYMBOL_GPL(__kvm_set_memory_region);

int kvm_set_memory_region(struct kvm *kvm,
1069
			  const struct kvm_userspace_memory_region *mem)
1070 1071 1072
{
	int r;

1073
	mutex_lock(&kvm->slots_lock);
1074
	r = __kvm_set_memory_region(kvm, mem);
1075
	mutex_unlock(&kvm->slots_lock);
1076 1077
	return r;
}
1078 1079
EXPORT_SYMBOL_GPL(kvm_set_memory_region);

1080 1081
static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
					  struct kvm_userspace_memory_region *mem)
1082
{
1083
	if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1084
		return -EINVAL;
1085

1086
	return kvm_set_memory_region(kvm, mem);
A
Avi Kivity 已提交
1087 1088
}

1089 1090
int kvm_get_dirty_log(struct kvm *kvm,
			struct kvm_dirty_log *log, int *is_dirty)
A
Avi Kivity 已提交
1091
{
1092
	struct kvm_memslots *slots;
A
Avi Kivity 已提交
1093
	struct kvm_memory_slot *memslot;
1094
	int r, i, as_id, id;
1095
	unsigned long n;
A
Avi Kivity 已提交
1096 1097 1098
	unsigned long any = 0;

	r = -EINVAL;
1099 1100 1101
	as_id = log->slot >> 16;
	id = (u16)log->slot;
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
A
Avi Kivity 已提交
1102 1103
		goto out;

1104 1105
	slots = __kvm_memslots(kvm, as_id);
	memslot = id_to_memslot(slots, id);
A
Avi Kivity 已提交
1106 1107 1108 1109
	r = -ENOENT;
	if (!memslot->dirty_bitmap)
		goto out;

1110
	n = kvm_dirty_bitmap_bytes(memslot);
A
Avi Kivity 已提交
1111

1112
	for (i = 0; !any && i < n/sizeof(long); ++i)
A
Avi Kivity 已提交
1113 1114 1115 1116 1117 1118
		any = memslot->dirty_bitmap[i];

	r = -EFAULT;
	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
		goto out;

1119 1120
	if (any)
		*is_dirty = 1;
A
Avi Kivity 已提交
1121 1122 1123 1124 1125

	r = 0;
out:
	return r;
}
1126
EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
A
Avi Kivity 已提交
1127

1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
/**
 * kvm_get_dirty_log_protect - get a snapshot of dirty pages, and if any pages
 *	are dirty write protect them for next write.
 * @kvm:	pointer to kvm instance
 * @log:	slot id and address to which we copy the log
 * @is_dirty:	flag set if any page is dirty
 *
 * We need to keep it in mind that VCPU threads can write to the bitmap
 * concurrently. So, to avoid losing track of dirty pages we keep the
 * following order:
 *
 *    1. Take a snapshot of the bit and clear it if needed.
 *    2. Write protect the corresponding page.
 *    3. Copy the snapshot to the userspace.
 *    4. Upon return caller flushes TLB's if needed.
 *
 * Between 2 and 4, the guest may write to the page using the remaining TLB
 * entry.  This is not a problem because the page is reported dirty using
 * the snapshot taken before and step 4 ensures that writes done after
 * exiting to userspace will be logged for the next call.
 *
 */
int kvm_get_dirty_log_protect(struct kvm *kvm,
			struct kvm_dirty_log *log, bool *is_dirty)
{
1154
	struct kvm_memslots *slots;
1155
	struct kvm_memory_slot *memslot;
1156
	int r, i, as_id, id;
1157 1158 1159 1160 1161
	unsigned long n;
	unsigned long *dirty_bitmap;
	unsigned long *dirty_bitmap_buffer;

	r = -EINVAL;
1162 1163 1164
	as_id = log->slot >> 16;
	id = (u16)log->slot;
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1165 1166
		goto out;

1167 1168
	slots = __kvm_memslots(kvm, as_id);
	memslot = id_to_memslot(slots, id);
1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193

	dirty_bitmap = memslot->dirty_bitmap;
	r = -ENOENT;
	if (!dirty_bitmap)
		goto out;

	n = kvm_dirty_bitmap_bytes(memslot);

	dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long);
	memset(dirty_bitmap_buffer, 0, n);

	spin_lock(&kvm->mmu_lock);
	*is_dirty = false;
	for (i = 0; i < n / sizeof(long); i++) {
		unsigned long mask;
		gfn_t offset;

		if (!dirty_bitmap[i])
			continue;

		*is_dirty = true;

		mask = xchg(&dirty_bitmap[i], 0);
		dirty_bitmap_buffer[i] = mask;

1194 1195 1196 1197 1198
		if (mask) {
			offset = i * BITS_PER_LONG;
			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
								offset, mask);
		}
1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213
	}

	spin_unlock(&kvm->mmu_lock);

	r = -EFAULT;
	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
		goto out;

	r = 0;
out:
	return r;
}
EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
#endif

1214 1215 1216 1217 1218
bool kvm_largepages_enabled(void)
{
	return largepages_enabled;
}

1219 1220 1221 1222 1223 1224
void kvm_disable_largepages(void)
{
	largepages_enabled = false;
}
EXPORT_SYMBOL_GPL(kvm_disable_largepages);

1225 1226 1227 1228
struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
{
	return __gfn_to_memslot(kvm_memslots(kvm), gfn);
}
A
Avi Kivity 已提交
1229
EXPORT_SYMBOL_GPL(gfn_to_memslot);
A
Avi Kivity 已提交
1230

1231 1232 1233 1234 1235
struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
{
	return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
}

1236
bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1237
{
1238
	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1239

1240
	if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1241
	      memslot->flags & KVM_MEMSLOT_INVALID)
1242
		return false;
1243

1244
	return true;
1245 1246 1247
}
EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);

J
Joerg Roedel 已提交
1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271
unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn)
{
	struct vm_area_struct *vma;
	unsigned long addr, size;

	size = PAGE_SIZE;

	addr = gfn_to_hva(kvm, gfn);
	if (kvm_is_error_hva(addr))
		return PAGE_SIZE;

	down_read(&current->mm->mmap_sem);
	vma = find_vma(current->mm, addr);
	if (!vma)
		goto out;

	size = vma_kernel_pagesize(vma);

out:
	up_read(&current->mm->mmap_sem);

	return size;
}

X
Xiao Guangrong 已提交
1272 1273 1274 1275 1276 1277 1278
static bool memslot_is_readonly(struct kvm_memory_slot *slot)
{
	return slot->flags & KVM_MEM_READONLY;
}

static unsigned long __gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
				       gfn_t *nr_pages, bool write)
I
Izik Eidus 已提交
1279
{
1280
	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
X
Xiao Guangrong 已提交
1281
		return KVM_HVA_ERR_BAD;
1282

X
Xiao Guangrong 已提交
1283 1284
	if (memslot_is_readonly(slot) && write)
		return KVM_HVA_ERR_RO_BAD;
1285 1286 1287 1288

	if (nr_pages)
		*nr_pages = slot->npages - (gfn - slot->base_gfn);

X
Xiao Guangrong 已提交
1289
	return __gfn_to_hva_memslot(slot, gfn);
I
Izik Eidus 已提交
1290
}
1291

X
Xiao Guangrong 已提交
1292 1293 1294 1295
static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
				     gfn_t *nr_pages)
{
	return __gfn_to_hva_many(slot, gfn, nr_pages, true);
I
Izik Eidus 已提交
1296
}
1297

X
Xiao Guangrong 已提交
1298
unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1299
					gfn_t gfn)
X
Xiao Guangrong 已提交
1300 1301 1302 1303 1304
{
	return gfn_to_hva_many(slot, gfn, NULL);
}
EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);

1305 1306
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
{
1307
	return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1308
}
1309
EXPORT_SYMBOL_GPL(gfn_to_hva);
I
Izik Eidus 已提交
1310

1311 1312 1313 1314 1315 1316
unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
{
	return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);

1317
/*
1318 1319
 * If writable is set to false, the hva returned by this function is only
 * allowed to be read.
1320
 */
1321 1322
unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
				      gfn_t gfn, bool *writable)
1323
{
1324 1325 1326
	unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);

	if (!kvm_is_error_hva(hva) && writable)
1327 1328
		*writable = !memslot_is_readonly(slot);

1329
	return hva;
1330 1331
}

1332 1333 1334 1335 1336 1337 1338
unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
{
	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);

	return gfn_to_hva_memslot_prot(slot, gfn, writable);
}

1339 1340 1341 1342 1343 1344 1345
unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
{
	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);

	return gfn_to_hva_memslot_prot(slot, gfn, writable);
}

1346 1347
static int get_user_page_nowait(unsigned long start, int write,
		struct page **page)
1348
{
L
Lorenzo Stoakes 已提交
1349
	int flags = FOLL_NOWAIT | FOLL_HWPOISON;
1350 1351 1352 1353

	if (write)
		flags |= FOLL_WRITE;

L
Lorenzo Stoakes 已提交
1354
	return get_user_pages(start, 1, flags, page, NULL);
1355 1356
}

1357 1358
static inline int check_user_page_hwpoison(unsigned long addr)
{
L
Lorenzo Stoakes 已提交
1359
	int rc, flags = FOLL_HWPOISON | FOLL_WRITE;
1360

L
Lorenzo Stoakes 已提交
1361
	rc = get_user_pages(addr, 1, flags, NULL, NULL);
1362 1363 1364
	return rc == -EHWPOISON;
}

X
Xiao Guangrong 已提交
1365 1366 1367 1368 1369
/*
 * The atomic path to get the writable pfn which will be stored in @pfn,
 * true indicates success, otherwise false is returned.
 */
static bool hva_to_pfn_fast(unsigned long addr, bool atomic, bool *async,
D
Dan Williams 已提交
1370
			    bool write_fault, bool *writable, kvm_pfn_t *pfn)
A
Avi Kivity 已提交
1371
{
1372
	struct page *page[1];
X
Xiao Guangrong 已提交
1373
	int npages;
A
Avi Kivity 已提交
1374

X
Xiao Guangrong 已提交
1375 1376
	if (!(async || atomic))
		return false;
1377

1378 1379 1380 1381 1382 1383 1384
	/*
	 * Fast pin a writable pfn only if it is a write fault request
	 * or the caller allows to map a writable pfn for a read fault
	 * request.
	 */
	if (!(write_fault || writable))
		return false;
1385

X
Xiao Guangrong 已提交
1386 1387 1388
	npages = __get_user_pages_fast(addr, 1, 1, page);
	if (npages == 1) {
		*pfn = page_to_pfn(page[0]);
1389

X
Xiao Guangrong 已提交
1390 1391 1392 1393
		if (writable)
			*writable = true;
		return true;
	}
1394

X
Xiao Guangrong 已提交
1395 1396
	return false;
}
1397

X
Xiao Guangrong 已提交
1398 1399 1400 1401 1402
/*
 * The slow path to get the pfn of the specified host virtual address,
 * 1 indicates success, -errno is returned if error is detected.
 */
static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault,
D
Dan Williams 已提交
1403
			   bool *writable, kvm_pfn_t *pfn)
X
Xiao Guangrong 已提交
1404 1405 1406
{
	struct page *page[1];
	int npages = 0;
1407

X
Xiao Guangrong 已提交
1408 1409 1410 1411 1412 1413 1414
	might_sleep();

	if (writable)
		*writable = write_fault;

	if (async) {
		down_read(&current->mm->mmap_sem);
1415
		npages = get_user_page_nowait(addr, write_fault, page);
X
Xiao Guangrong 已提交
1416
		up_read(&current->mm->mmap_sem);
1417 1418 1419 1420 1421 1422
	} else {
		unsigned int flags = FOLL_TOUCH | FOLL_HWPOISON;

		if (write_fault)
			flags |= FOLL_WRITE;

1423
		npages = __get_user_pages_unlocked(current, current->mm, addr, 1,
1424 1425
						   page, flags);
	}
X
Xiao Guangrong 已提交
1426 1427 1428 1429
	if (npages != 1)
		return npages;

	/* map read fault as writable if possible */
1430
	if (unlikely(!write_fault) && writable) {
X
Xiao Guangrong 已提交
1431 1432 1433 1434 1435 1436 1437
		struct page *wpage[1];

		npages = __get_user_pages_fast(addr, 1, 1, wpage);
		if (npages == 1) {
			*writable = true;
			put_page(page[0]);
			page[0] = wpage[0];
1438
		}
X
Xiao Guangrong 已提交
1439 1440

		npages = 1;
1441
	}
X
Xiao Guangrong 已提交
1442 1443 1444
	*pfn = page_to_pfn(page[0]);
	return npages;
}
I
Izik Eidus 已提交
1445

X
Xiao Guangrong 已提交
1446 1447 1448 1449
static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
{
	if (unlikely(!(vma->vm_flags & VM_READ)))
		return false;
1450

X
Xiao Guangrong 已提交
1451 1452
	if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
		return false;
1453

X
Xiao Guangrong 已提交
1454 1455
	return true;
}
1456

1457 1458 1459 1460
static int hva_to_pfn_remapped(struct vm_area_struct *vma,
			       unsigned long addr, bool *async,
			       bool write_fault, kvm_pfn_t *p_pfn)
{
1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499
	unsigned long pfn;
	int r;

	r = follow_pfn(vma, addr, &pfn);
	if (r) {
		/*
		 * get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
		 * not call the fault handler, so do it here.
		 */
		bool unlocked = false;
		r = fixup_user_fault(current, current->mm, addr,
				     (write_fault ? FAULT_FLAG_WRITE : 0),
				     &unlocked);
		if (unlocked)
			return -EAGAIN;
		if (r)
			return r;

		r = follow_pfn(vma, addr, &pfn);
		if (r)
			return r;

	}


	/*
	 * Get a reference here because callers of *hva_to_pfn* and
	 * *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
	 * returned pfn.  This is only needed if the VMA has VM_MIXEDMAP
	 * set, but the kvm_get_pfn/kvm_release_pfn_clean pair will
	 * simply do nothing for reserved pfns.
	 *
	 * Whoever called remap_pfn_range is also going to call e.g.
	 * unmap_mapping_range before the underlying pages are freed,
	 * causing a call to our MMU notifier.
	 */ 
	kvm_get_pfn(pfn);

	*p_pfn = pfn;
1500 1501 1502
	return 0;
}

1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516
/*
 * Pin guest page in memory and return its pfn.
 * @addr: host virtual address which maps memory to the guest
 * @atomic: whether this function can sleep
 * @async: whether this function need to wait IO complete if the
 *         host page is not in the memory
 * @write_fault: whether we should get a writable host page
 * @writable: whether it allows to map a writable host page for !@write_fault
 *
 * The function will map a writable host page for these two cases:
 * 1): @write_fault = true
 * 2): @write_fault = false && @writable, @writable will tell the caller
 *     whether the mapping is writable.
 */
D
Dan Williams 已提交
1517
static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
X
Xiao Guangrong 已提交
1518 1519 1520
			bool write_fault, bool *writable)
{
	struct vm_area_struct *vma;
D
Dan Williams 已提交
1521
	kvm_pfn_t pfn = 0;
1522
	int npages, r;
1523

X
Xiao Guangrong 已提交
1524 1525
	/* we can do it either atomically or asynchronously, not both */
	BUG_ON(atomic && async);
1526

X
Xiao Guangrong 已提交
1527 1528 1529 1530 1531 1532 1533 1534 1535
	if (hva_to_pfn_fast(addr, atomic, async, write_fault, writable, &pfn))
		return pfn;

	if (atomic)
		return KVM_PFN_ERR_FAULT;

	npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn);
	if (npages == 1)
		return pfn;
1536

X
Xiao Guangrong 已提交
1537 1538 1539 1540 1541 1542 1543
	down_read(&current->mm->mmap_sem);
	if (npages == -EHWPOISON ||
	      (!async && check_user_page_hwpoison(addr))) {
		pfn = KVM_PFN_ERR_HWPOISON;
		goto exit;
	}

1544
retry:
X
Xiao Guangrong 已提交
1545 1546 1547 1548
	vma = find_vma_intersection(current->mm, addr, addr + 1);

	if (vma == NULL)
		pfn = KVM_PFN_ERR_FAULT;
1549 1550
	else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) {
		r = hva_to_pfn_remapped(vma, addr, async, write_fault, &pfn);
1551 1552
		if (r == -EAGAIN)
			goto retry;
1553 1554
		if (r < 0)
			pfn = KVM_PFN_ERR_FAULT;
X
Xiao Guangrong 已提交
1555
	} else {
X
Xiao Guangrong 已提交
1556
		if (async && vma_is_valid(vma, write_fault))
X
Xiao Guangrong 已提交
1557 1558 1559 1560 1561
			*async = true;
		pfn = KVM_PFN_ERR_FAULT;
	}
exit:
	up_read(&current->mm->mmap_sem);
1562
	return pfn;
1563 1564
}

D
Dan Williams 已提交
1565 1566 1567
kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn,
			       bool atomic, bool *async, bool write_fault,
			       bool *writable)
1568
{
X
Xiao Guangrong 已提交
1569 1570
	unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);

1571 1572 1573
	if (addr == KVM_HVA_ERR_RO_BAD) {
		if (writable)
			*writable = false;
X
Xiao Guangrong 已提交
1574
		return KVM_PFN_ERR_RO_FAULT;
1575
	}
X
Xiao Guangrong 已提交
1576

1577 1578 1579
	if (kvm_is_error_hva(addr)) {
		if (writable)
			*writable = false;
1580
		return KVM_PFN_NOSLOT;
1581
	}
X
Xiao Guangrong 已提交
1582 1583 1584 1585 1586 1587 1588 1589 1590

	/* Do not map writable pfn in the readonly memslot. */
	if (writable && memslot_is_readonly(slot)) {
		*writable = false;
		writable = NULL;
	}

	return hva_to_pfn(addr, atomic, async, write_fault,
			  writable);
1591
}
1592
EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
1593

D
Dan Williams 已提交
1594
kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1595 1596
		      bool *writable)
{
P
Paolo Bonzini 已提交
1597 1598
	return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
				    write_fault, writable);
1599 1600 1601
}
EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);

D
Dan Williams 已提交
1602
kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1603
{
X
Xiao Guangrong 已提交
1604
	return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1605
}
P
Paolo Bonzini 已提交
1606
EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
1607

D
Dan Williams 已提交
1608
kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1609
{
X
Xiao Guangrong 已提交
1610
	return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1611
}
1612
EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1613

D
Dan Williams 已提交
1614
kvm_pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
P
Paolo Bonzini 已提交
1615 1616 1617 1618 1619
{
	return gfn_to_pfn_memslot_atomic(gfn_to_memslot(kvm, gfn), gfn);
}
EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic);

D
Dan Williams 已提交
1620
kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
1621 1622 1623 1624 1625
{
	return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);

D
Dan Williams 已提交
1626
kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
P
Paolo Bonzini 已提交
1627 1628 1629 1630 1631
{
	return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
}
EXPORT_SYMBOL_GPL(gfn_to_pfn);

D
Dan Williams 已提交
1632
kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1633 1634 1635 1636 1637
{
	return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);

1638 1639
int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
			    struct page **pages, int nr_pages)
1640 1641 1642 1643
{
	unsigned long addr;
	gfn_t entry;

1644
	addr = gfn_to_hva_many(slot, gfn, &entry);
1645 1646 1647 1648 1649 1650 1651 1652 1653 1654
	if (kvm_is_error_hva(addr))
		return -1;

	if (entry < nr_pages)
		return 0;

	return __get_user_pages_fast(addr, nr_pages, 1, pages);
}
EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);

D
Dan Williams 已提交
1655
static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
X
Xiao Guangrong 已提交
1656
{
1657
	if (is_error_noslot_pfn(pfn))
1658
		return KVM_ERR_PTR_BAD_PAGE;
X
Xiao Guangrong 已提交
1659

1660
	if (kvm_is_reserved_pfn(pfn)) {
1661
		WARN_ON(1);
1662
		return KVM_ERR_PTR_BAD_PAGE;
1663
	}
X
Xiao Guangrong 已提交
1664 1665 1666 1667

	return pfn_to_page(pfn);
}

1668 1669
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
{
D
Dan Williams 已提交
1670
	kvm_pfn_t pfn;
1671 1672 1673

	pfn = gfn_to_pfn(kvm, gfn);

X
Xiao Guangrong 已提交
1674
	return kvm_pfn_to_page(pfn);
A
Avi Kivity 已提交
1675 1676 1677
}
EXPORT_SYMBOL_GPL(gfn_to_page);

1678 1679
struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
{
D
Dan Williams 已提交
1680
	kvm_pfn_t pfn;
1681 1682 1683 1684 1685 1686 1687

	pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);

	return kvm_pfn_to_page(pfn);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page);

1688 1689
void kvm_release_page_clean(struct page *page)
{
1690 1691
	WARN_ON(is_error_page(page));

1692
	kvm_release_pfn_clean(page_to_pfn(page));
1693 1694 1695
}
EXPORT_SYMBOL_GPL(kvm_release_page_clean);

D
Dan Williams 已提交
1696
void kvm_release_pfn_clean(kvm_pfn_t pfn)
1697
{
1698
	if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
1699
		put_page(pfn_to_page(pfn));
1700 1701 1702
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);

1703
void kvm_release_page_dirty(struct page *page)
1704
{
X
Xiao Guangrong 已提交
1705 1706
	WARN_ON(is_error_page(page));

1707 1708 1709 1710
	kvm_release_pfn_dirty(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_dirty);

D
Dan Williams 已提交
1711
static void kvm_release_pfn_dirty(kvm_pfn_t pfn)
1712 1713 1714 1715 1716
{
	kvm_set_pfn_dirty(pfn);
	kvm_release_pfn_clean(pfn);
}

D
Dan Williams 已提交
1717
void kvm_set_pfn_dirty(kvm_pfn_t pfn)
1718
{
1719
	if (!kvm_is_reserved_pfn(pfn)) {
1720
		struct page *page = pfn_to_page(pfn);
1721

1722 1723 1724
		if (!PageReserved(page))
			SetPageDirty(page);
	}
1725
}
1726 1727
EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);

D
Dan Williams 已提交
1728
void kvm_set_pfn_accessed(kvm_pfn_t pfn)
1729
{
1730
	if (!kvm_is_reserved_pfn(pfn))
1731
		mark_page_accessed(pfn_to_page(pfn));
1732 1733 1734
}
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);

D
Dan Williams 已提交
1735
void kvm_get_pfn(kvm_pfn_t pfn)
1736
{
1737
	if (!kvm_is_reserved_pfn(pfn))
1738
		get_page(pfn_to_page(pfn));
1739 1740
}
EXPORT_SYMBOL_GPL(kvm_get_pfn);
1741

1742 1743 1744 1745 1746 1747 1748 1749
static int next_segment(unsigned long len, int offset)
{
	if (len > PAGE_SIZE - offset)
		return PAGE_SIZE - offset;
	else
		return len;
}

1750 1751
static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
				 void *data, int offset, int len)
1752
{
1753 1754
	int r;
	unsigned long addr;
1755

1756
	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1757 1758
	if (kvm_is_error_hva(addr))
		return -EFAULT;
1759
	r = __copy_from_user(data, (void __user *)addr + offset, len);
1760
	if (r)
1761 1762 1763
		return -EFAULT;
	return 0;
}
1764 1765 1766 1767 1768 1769 1770 1771

int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
			int len)
{
	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);

	return __kvm_read_guest_page(slot, gfn, data, offset, len);
}
1772 1773
EXPORT_SYMBOL_GPL(kvm_read_guest_page);

1774 1775 1776 1777 1778 1779 1780 1781 1782
int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
			     int offset, int len)
{
	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);

	return __kvm_read_guest_page(slot, gfn, data, offset, len);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);

1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802
int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	int seg;
	int offset = offset_in_page(gpa);
	int ret;

	while ((seg = next_segment(len, offset)) != 0) {
		ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
		if (ret < 0)
			return ret;
		offset = 0;
		len -= seg;
		data += seg;
		++gfn;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_read_guest);

1803
int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
1804 1805
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
1806
	int seg;
1807
	int offset = offset_in_page(gpa);
1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821
	int ret;

	while ((seg = next_segment(len, offset)) != 0) {
		ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
		if (ret < 0)
			return ret;
		offset = 0;
		len -= seg;
		data += seg;
		++gfn;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
1822

1823 1824 1825 1826 1827 1828 1829
static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
			           void *data, int offset, unsigned long len)
{
	int r;
	unsigned long addr;

	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
1830 1831
	if (kvm_is_error_hva(addr))
		return -EFAULT;
1832
	pagefault_disable();
1833
	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
1834
	pagefault_enable();
1835 1836 1837 1838 1839
	if (r)
		return -EFAULT;
	return 0;
}

1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863
int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
			  unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
	int offset = offset_in_page(gpa);

	return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
}
EXPORT_SYMBOL_GPL(kvm_read_guest_atomic);

int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
			       void *data, unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
	int offset = offset_in_page(gpa);

	return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);

static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
			          const void *data, int offset, int len)
1864
{
1865 1866
	int r;
	unsigned long addr;
1867

1868
	addr = gfn_to_hva_memslot(memslot, gfn);
1869 1870
	if (kvm_is_error_hva(addr))
		return -EFAULT;
1871
	r = __copy_to_user((void __user *)addr + offset, data, len);
1872
	if (r)
1873
		return -EFAULT;
1874
	mark_page_dirty_in_slot(memslot, gfn);
1875 1876
	return 0;
}
1877 1878 1879 1880 1881 1882 1883 1884

int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
			 const void *data, int offset, int len)
{
	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);

	return __kvm_write_guest_page(slot, gfn, data, offset, len);
}
1885 1886
EXPORT_SYMBOL_GPL(kvm_write_guest_page);

1887 1888 1889 1890 1891 1892 1893 1894 1895
int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
			      const void *data, int offset, int len)
{
	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);

	return __kvm_write_guest_page(slot, gfn, data, offset, len);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);

1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914
int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
		    unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	int seg;
	int offset = offset_in_page(gpa);
	int ret;

	while ((seg = next_segment(len, offset)) != 0) {
		ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
		if (ret < 0)
			return ret;
		offset = 0;
		len -= seg;
		data += seg;
		++gfn;
	}
	return 0;
}
1915
EXPORT_SYMBOL_GPL(kvm_write_guest);
1916

1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937
int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
		         unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	int seg;
	int offset = offset_in_page(gpa);
	int ret;

	while ((seg = next_segment(len, offset)) != 0) {
		ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
		if (ret < 0)
			return ret;
		offset = 0;
		len -= seg;
		data += seg;
		++gfn;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);

1938
int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
1939
			      gpa_t gpa, unsigned long len)
1940 1941 1942
{
	struct kvm_memslots *slots = kvm_memslots(kvm);
	int offset = offset_in_page(gpa);
1943 1944 1945 1946
	gfn_t start_gfn = gpa >> PAGE_SHIFT;
	gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
	gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
	gfn_t nr_pages_avail;
1947 1948 1949

	ghc->gpa = gpa;
	ghc->generation = slots->generation;
1950 1951
	ghc->len = len;
	ghc->memslot = gfn_to_memslot(kvm, start_gfn);
1952 1953
	ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
	if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
1954
		ghc->hva += offset;
1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970
	} else {
		/*
		 * If the requested region crosses two memslots, we still
		 * verify that the entire region is valid here.
		 */
		while (start_gfn <= end_gfn) {
			ghc->memslot = gfn_to_memslot(kvm, start_gfn);
			ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
						   &nr_pages_avail);
			if (kvm_is_error_hva(ghc->hva))
				return -EFAULT;
			start_gfn += nr_pages_avail;
		}
		/* Use the slow path for cross page reads and writes. */
		ghc->memslot = NULL;
	}
1971 1972 1973 1974 1975 1976 1977 1978 1979 1980
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);

int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
			   void *data, unsigned long len)
{
	struct kvm_memslots *slots = kvm_memslots(kvm);
	int r;

1981 1982
	BUG_ON(len > ghc->len);

1983
	if (slots->generation != ghc->generation)
1984 1985 1986 1987
		kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);

	if (unlikely(!ghc->memslot))
		return kvm_write_guest(kvm, ghc->gpa, data, len);
1988 1989 1990 1991

	if (kvm_is_error_hva(ghc->hva))
		return -EFAULT;

1992
	r = __copy_to_user((void __user *)ghc->hva, data, len);
1993 1994
	if (r)
		return -EFAULT;
1995
	mark_page_dirty_in_slot(ghc->memslot, ghc->gpa >> PAGE_SHIFT);
1996 1997 1998 1999 2000

	return 0;
}
EXPORT_SYMBOL_GPL(kvm_write_guest_cached);

2001 2002 2003 2004 2005 2006
int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
			   void *data, unsigned long len)
{
	struct kvm_memslots *slots = kvm_memslots(kvm);
	int r;

2007 2008
	BUG_ON(len > ghc->len);

2009
	if (slots->generation != ghc->generation)
2010 2011 2012 2013
		kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);

	if (unlikely(!ghc->memslot))
		return kvm_read_guest(kvm, ghc->gpa, data, len);
2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

	if (kvm_is_error_hva(ghc->hva))
		return -EFAULT;

	r = __copy_from_user(data, (void __user *)ghc->hva, len);
	if (r)
		return -EFAULT;

	return 0;
}
EXPORT_SYMBOL_GPL(kvm_read_guest_cached);

2026 2027
int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
{
2028 2029 2030
	const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));

	return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
}
EXPORT_SYMBOL_GPL(kvm_clear_guest_page);

int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
	int seg;
	int offset = offset_in_page(gpa);
	int ret;

2041
	while ((seg = next_segment(len, offset)) != 0) {
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052
		ret = kvm_clear_guest_page(kvm, gfn, offset, seg);
		if (ret < 0)
			return ret;
		offset = 0;
		len -= seg;
		++gfn;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_clear_guest);

2053
static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
2054
				    gfn_t gfn)
A
Avi Kivity 已提交
2055
{
R
Rusty Russell 已提交
2056 2057
	if (memslot && memslot->dirty_bitmap) {
		unsigned long rel_gfn = gfn - memslot->base_gfn;
A
Avi Kivity 已提交
2058

2059
		set_bit_le(rel_gfn, memslot->dirty_bitmap);
A
Avi Kivity 已提交
2060 2061 2062
	}
}

2063 2064 2065 2066 2067
void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
{
	struct kvm_memory_slot *memslot;

	memslot = gfn_to_memslot(kvm, gfn);
2068
	mark_page_dirty_in_slot(memslot, gfn);
2069
}
2070
EXPORT_SYMBOL_GPL(mark_page_dirty);
2071

2072 2073 2074 2075 2076 2077 2078 2079 2080
void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
{
	struct kvm_memory_slot *memslot;

	memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
	mark_page_dirty_in_slot(memslot, gfn);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);

W
Wanpeng Li 已提交
2081 2082
static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
{
2083
	unsigned int old, val, grow;
W
Wanpeng Li 已提交
2084

2085
	old = val = vcpu->halt_poll_ns;
2086
	grow = READ_ONCE(halt_poll_ns_grow);
W
Wanpeng Li 已提交
2087
	/* 10us base */
2088
	if (val == 0 && grow)
W
Wanpeng Li 已提交
2089 2090
		val = 10000;
	else
2091
		val *= grow;
W
Wanpeng Li 已提交
2092

2093 2094 2095
	if (val > halt_poll_ns)
		val = halt_poll_ns;

W
Wanpeng Li 已提交
2096
	vcpu->halt_poll_ns = val;
2097
	trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
W
Wanpeng Li 已提交
2098 2099 2100 2101
}

static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
{
2102
	unsigned int old, val, shrink;
W
Wanpeng Li 已提交
2103

2104
	old = val = vcpu->halt_poll_ns;
2105 2106
	shrink = READ_ONCE(halt_poll_ns_shrink);
	if (shrink == 0)
W
Wanpeng Li 已提交
2107 2108
		val = 0;
	else
2109
		val /= shrink;
W
Wanpeng Li 已提交
2110 2111

	vcpu->halt_poll_ns = val;
2112
	trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
W
Wanpeng Li 已提交
2113 2114
}

2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128
static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
{
	if (kvm_arch_vcpu_runnable(vcpu)) {
		kvm_make_request(KVM_REQ_UNHALT, vcpu);
		return -EINTR;
	}
	if (kvm_cpu_has_pending_timer(vcpu))
		return -EINTR;
	if (signal_pending(current))
		return -EINTR;

	return 0;
}

E
Eddie Dong 已提交
2129 2130 2131
/*
 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 */
2132
void kvm_vcpu_block(struct kvm_vcpu *vcpu)
2133
{
2134
	ktime_t start, cur;
2135
	DECLARE_SWAITQUEUE(wait);
2136
	bool waited = false;
W
Wanpeng Li 已提交
2137
	u64 block_ns;
2138 2139

	start = cur = ktime_get();
W
Wanpeng Li 已提交
2140 2141
	if (vcpu->halt_poll_ns) {
		ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
2142

2143
		++vcpu->stat.halt_attempted_poll;
2144 2145 2146 2147 2148 2149 2150
		do {
			/*
			 * This sets KVM_REQ_UNHALT if an interrupt
			 * arrives.
			 */
			if (kvm_vcpu_check_block(vcpu) < 0) {
				++vcpu->stat.halt_successful_poll;
2151 2152
				if (!vcpu_valid_wakeup(vcpu))
					++vcpu->stat.halt_poll_invalid;
2153 2154 2155 2156 2157
				goto out;
			}
			cur = ktime_get();
		} while (single_task_running() && ktime_before(cur, stop));
	}
2158

2159 2160
	kvm_arch_vcpu_blocking(vcpu);

2161
	for (;;) {
2162
		prepare_to_swait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
2163

2164
		if (kvm_vcpu_check_block(vcpu) < 0)
2165 2166
			break;

2167
		waited = true;
E
Eddie Dong 已提交
2168 2169
		schedule();
	}
2170

2171
	finish_swait(&vcpu->wq, &wait);
2172 2173
	cur = ktime_get();

2174
	kvm_arch_vcpu_unblocking(vcpu);
2175
out:
W
Wanpeng Li 已提交
2176 2177
	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);

2178 2179 2180
	if (!vcpu_valid_wakeup(vcpu))
		shrink_halt_poll_ns(vcpu);
	else if (halt_poll_ns) {
W
Wanpeng Li 已提交
2181 2182 2183
		if (block_ns <= vcpu->halt_poll_ns)
			;
		/* we had a long block, shrink polling */
2184
		else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns)
W
Wanpeng Li 已提交
2185 2186 2187 2188 2189
			shrink_halt_poll_ns(vcpu);
		/* we had a short halt and our poll time is too small */
		else if (vcpu->halt_poll_ns < halt_poll_ns &&
			block_ns < halt_poll_ns)
			grow_halt_poll_ns(vcpu);
2190 2191
	} else
		vcpu->halt_poll_ns = 0;
W
Wanpeng Li 已提交
2192

2193 2194
	trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu));
	kvm_arch_vcpu_block_finish(vcpu);
E
Eddie Dong 已提交
2195
}
2196
EXPORT_SYMBOL_GPL(kvm_vcpu_block);
E
Eddie Dong 已提交
2197

2198
#ifndef CONFIG_S390
2199
void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
2200
{
2201
	struct swait_queue_head *wqp;
2202 2203

	wqp = kvm_arch_vcpu_wq(vcpu);
2204 2205
	if (swait_active(wqp)) {
		swake_up(wqp);
2206 2207 2208
		++vcpu->stat.halt_wakeup;
	}

2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220
}
EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);

/*
 * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
 */
void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
{
	int me;
	int cpu = vcpu->cpu;

	kvm_vcpu_wake_up(vcpu);
2221 2222 2223 2224 2225 2226
	me = get_cpu();
	if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
		if (kvm_arch_vcpu_should_kick(vcpu))
			smp_send_reschedule(cpu);
	put_cpu();
}
2227
EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
2228
#endif /* !CONFIG_S390 */
2229

2230
int kvm_vcpu_yield_to(struct kvm_vcpu *target)
2231 2232 2233
{
	struct pid *pid;
	struct task_struct *task = NULL;
2234
	int ret = 0;
2235 2236 2237 2238

	rcu_read_lock();
	pid = rcu_dereference(target->pid);
	if (pid)
2239
		task = get_pid_task(pid, PIDTYPE_PID);
2240 2241
	rcu_read_unlock();
	if (!task)
2242 2243
		return ret;
	ret = yield_to(task, 1);
2244
	put_task_struct(task);
2245 2246

	return ret;
2247 2248 2249
}
EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);

2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271
/*
 * Helper that checks whether a VCPU is eligible for directed yield.
 * Most eligible candidate to yield is decided by following heuristics:
 *
 *  (a) VCPU which has not done pl-exit or cpu relax intercepted recently
 *  (preempted lock holder), indicated by @in_spin_loop.
 *  Set at the beiginning and cleared at the end of interception/PLE handler.
 *
 *  (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
 *  chance last time (mostly it has become eligible now since we have probably
 *  yielded to lockholder in last iteration. This is done by toggling
 *  @dy_eligible each time a VCPU checked for eligibility.)
 *
 *  Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
 *  to preempted lock-holder could result in wrong VCPU selection and CPU
 *  burning. Giving priority for a potential lock-holder increases lock
 *  progress.
 *
 *  Since algorithm is based on heuristics, accessing another VCPU data without
 *  locking does not harm. It may result in trying to yield to  same VCPU, fail
 *  and continue with next VCPU and so on.
 */
2272
static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
2273
{
2274
#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2275 2276 2277
	bool eligible;

	eligible = !vcpu->spin_loop.in_spin_loop ||
2278
		    vcpu->spin_loop.dy_eligible;
2279 2280 2281 2282 2283

	if (vcpu->spin_loop.in_spin_loop)
		kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);

	return eligible;
2284 2285
#else
	return true;
2286
#endif
2287
}
2288

2289
void kvm_vcpu_on_spin(struct kvm_vcpu *me)
Z
Zhai, Edwin 已提交
2290
{
2291 2292 2293 2294
	struct kvm *kvm = me->kvm;
	struct kvm_vcpu *vcpu;
	int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
	int yielded = 0;
2295
	int try = 3;
2296 2297
	int pass;
	int i;
Z
Zhai, Edwin 已提交
2298

2299
	kvm_vcpu_set_in_spin_loop(me, true);
2300 2301 2302 2303 2304 2305 2306
	/*
	 * We boost the priority of a VCPU that is runnable but not
	 * currently running, because it got preempted by something
	 * else and called schedule in __vcpu_run.  Hopefully that
	 * VCPU is holding the lock that we need and will release it.
	 * We approximate round-robin by starting at the last boosted VCPU.
	 */
2307
	for (pass = 0; pass < 2 && !yielded && try; pass++) {
2308
		kvm_for_each_vcpu(i, vcpu, kvm) {
2309
			if (!pass && i <= last_boosted_vcpu) {
2310 2311 2312 2313
				i = last_boosted_vcpu;
				continue;
			} else if (pass && i > last_boosted_vcpu)
				break;
2314 2315
			if (!ACCESS_ONCE(vcpu->preempted))
				continue;
2316 2317
			if (vcpu == me)
				continue;
2318
			if (swait_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
2319
				continue;
2320 2321
			if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
				continue;
2322 2323 2324

			yielded = kvm_vcpu_yield_to(vcpu);
			if (yielded > 0) {
2325 2326
				kvm->last_boosted_vcpu = i;
				break;
2327 2328 2329 2330
			} else if (yielded < 0) {
				try--;
				if (!try)
					break;
2331 2332 2333
			}
		}
	}
2334
	kvm_vcpu_set_in_spin_loop(me, false);
2335 2336 2337

	/* Ensure vcpu is not eligible during next spinloop */
	kvm_vcpu_set_dy_eligible(me, false);
Z
Zhai, Edwin 已提交
2338 2339 2340
}
EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);

2341
static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
2342 2343 2344 2345
{
	struct kvm_vcpu *vcpu = vma->vm_file->private_data;
	struct page *page;

2346
	if (vmf->pgoff == 0)
2347
		page = virt_to_page(vcpu->run);
A
Avi Kivity 已提交
2348
#ifdef CONFIG_X86
2349
	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
2350
		page = virt_to_page(vcpu->arch.pio_data);
2351 2352 2353 2354
#endif
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
A
Avi Kivity 已提交
2355
#endif
2356
	else
2357
		return kvm_arch_vcpu_fault(vcpu, vmf);
2358
	get_page(page);
2359 2360
	vmf->page = page;
	return 0;
2361 2362
}

2363
static const struct vm_operations_struct kvm_vcpu_vm_ops = {
2364
	.fault = kvm_vcpu_fault,
2365 2366 2367 2368 2369 2370 2371 2372
};

static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
{
	vma->vm_ops = &kvm_vcpu_vm_ops;
	return 0;
}

A
Avi Kivity 已提交
2373 2374 2375 2376
static int kvm_vcpu_release(struct inode *inode, struct file *filp)
{
	struct kvm_vcpu *vcpu = filp->private_data;

2377
	debugfs_remove_recursive(vcpu->debugfs_dentry);
A
Al Viro 已提交
2378
	kvm_put_kvm(vcpu->kvm);
A
Avi Kivity 已提交
2379 2380 2381
	return 0;
}

2382
static struct file_operations kvm_vcpu_fops = {
A
Avi Kivity 已提交
2383 2384
	.release        = kvm_vcpu_release,
	.unlocked_ioctl = kvm_vcpu_ioctl,
2385
#ifdef CONFIG_KVM_COMPAT
2386 2387
	.compat_ioctl   = kvm_vcpu_compat_ioctl,
#endif
2388
	.mmap           = kvm_vcpu_mmap,
2389
	.llseek		= noop_llseek,
A
Avi Kivity 已提交
2390 2391 2392 2393 2394 2395 2396
};

/*
 * Allocates an inode for the vcpu.
 */
static int create_vcpu_fd(struct kvm_vcpu *vcpu)
{
2397
	return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
A
Avi Kivity 已提交
2398 2399
}

2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425
static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
{
	char dir_name[ITOA_MAX_LEN * 2];
	int ret;

	if (!kvm_arch_has_vcpu_debugfs())
		return 0;

	if (!debugfs_initialized())
		return 0;

	snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
	vcpu->debugfs_dentry = debugfs_create_dir(dir_name,
								vcpu->kvm->debugfs_dentry);
	if (!vcpu->debugfs_dentry)
		return -ENOMEM;

	ret = kvm_arch_create_vcpu_debugfs(vcpu);
	if (ret < 0) {
		debugfs_remove_recursive(vcpu->debugfs_dentry);
		return ret;
	}

	return 0;
}

2426 2427 2428
/*
 * Creates some virtual cpus.  Good luck creating more than one.
 */
2429
static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
2430 2431
{
	int r;
2432
	struct kvm_vcpu *vcpu;
2433

G
Greg Kurz 已提交
2434
	if (id >= KVM_MAX_VCPU_ID)
2435 2436
		return -EINVAL;

2437 2438 2439 2440 2441 2442 2443 2444 2445
	mutex_lock(&kvm->lock);
	if (kvm->created_vcpus == KVM_MAX_VCPUS) {
		mutex_unlock(&kvm->lock);
		return -EINVAL;
	}

	kvm->created_vcpus++;
	mutex_unlock(&kvm->lock);

2446
	vcpu = kvm_arch_vcpu_create(kvm, id);
2447 2448 2449 2450
	if (IS_ERR(vcpu)) {
		r = PTR_ERR(vcpu);
		goto vcpu_decrement;
	}
2451

2452 2453
	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);

2454 2455
	r = kvm_arch_vcpu_setup(vcpu);
	if (r)
2456
		goto vcpu_destroy;
2457

2458 2459 2460 2461
	r = kvm_create_vcpu_debugfs(vcpu);
	if (r)
		goto vcpu_destroy;

S
Shaohua Li 已提交
2462
	mutex_lock(&kvm->lock);
2463 2464 2465 2466
	if (kvm_get_vcpu_by_id(kvm, id)) {
		r = -EEXIST;
		goto unlock_vcpu_destroy;
	}
2467 2468

	BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
2469

R
Rusty Russell 已提交
2470
	/* Now it's all set up, let userspace reach it */
A
Al Viro 已提交
2471
	kvm_get_kvm(kvm);
A
Avi Kivity 已提交
2472
	r = create_vcpu_fd(vcpu);
2473 2474
	if (r < 0) {
		kvm_put_kvm(kvm);
2475
		goto unlock_vcpu_destroy;
2476 2477 2478
	}

	kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
2479 2480 2481 2482 2483

	/*
	 * Pairs with smp_rmb() in kvm_get_vcpu.  Write kvm->vcpus
	 * before kvm->online_vcpu's incremented value.
	 */
2484 2485 2486 2487
	smp_wmb();
	atomic_inc(&kvm->online_vcpus);

	mutex_unlock(&kvm->lock);
2488
	kvm_arch_vcpu_postcreate(vcpu);
R
Rusty Russell 已提交
2489
	return r;
2490

2491
unlock_vcpu_destroy:
2492
	mutex_unlock(&kvm->lock);
2493
	debugfs_remove_recursive(vcpu->debugfs_dentry);
2494
vcpu_destroy:
2495
	kvm_arch_vcpu_destroy(vcpu);
2496 2497 2498 2499
vcpu_decrement:
	mutex_lock(&kvm->lock);
	kvm->created_vcpus--;
	mutex_unlock(&kvm->lock);
2500 2501 2502
	return r;
}

A
Avi Kivity 已提交
2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513
static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
{
	if (sigset) {
		sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
		vcpu->sigset_active = 1;
		vcpu->sigset = *sigset;
	} else
		vcpu->sigset_active = 0;
	return 0;
}

A
Avi Kivity 已提交
2514 2515
static long kvm_vcpu_ioctl(struct file *filp,
			   unsigned int ioctl, unsigned long arg)
A
Avi Kivity 已提交
2516
{
A
Avi Kivity 已提交
2517
	struct kvm_vcpu *vcpu = filp->private_data;
A
Al Viro 已提交
2518
	void __user *argp = (void __user *)arg;
2519
	int r;
2520 2521
	struct kvm_fpu *fpu = NULL;
	struct kvm_sregs *kvm_sregs = NULL;
A
Avi Kivity 已提交
2522

2523 2524
	if (vcpu->kvm->mm != current->mm)
		return -EIO;
2525

2526 2527 2528
	if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
		return -EINVAL;

2529
#if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
2530 2531 2532 2533
	/*
	 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
	 * so vcpu_load() would break it.
	 */
2534
	if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_S390_IRQ || ioctl == KVM_INTERRUPT)
2535 2536 2537 2538
		return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
#endif


2539 2540 2541
	r = vcpu_load(vcpu);
	if (r)
		return r;
A
Avi Kivity 已提交
2542
	switch (ioctl) {
2543
	case KVM_RUN:
2544 2545 2546
		r = -EINVAL;
		if (arg)
			goto out;
2547 2548 2549 2550
		if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) {
			/* The thread running this VCPU changed. */
			struct pid *oldpid = vcpu->pid;
			struct pid *newpid = get_task_pid(current, PIDTYPE_PID);
2551

2552 2553 2554 2555 2556
			rcu_assign_pointer(vcpu->pid, newpid);
			if (oldpid)
				synchronize_rcu();
			put_pid(oldpid);
		}
2557
		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2558
		trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
A
Avi Kivity 已提交
2559 2560
		break;
	case KVM_GET_REGS: {
2561
		struct kvm_regs *kvm_regs;
A
Avi Kivity 已提交
2562

2563 2564 2565
		r = -ENOMEM;
		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
		if (!kvm_regs)
A
Avi Kivity 已提交
2566
			goto out;
2567 2568 2569
		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
		if (r)
			goto out_free1;
A
Avi Kivity 已提交
2570
		r = -EFAULT;
2571 2572
		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
			goto out_free1;
A
Avi Kivity 已提交
2573
		r = 0;
2574 2575
out_free1:
		kfree(kvm_regs);
A
Avi Kivity 已提交
2576 2577 2578
		break;
	}
	case KVM_SET_REGS: {
2579
		struct kvm_regs *kvm_regs;
A
Avi Kivity 已提交
2580

2581
		r = -ENOMEM;
2582 2583 2584
		kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
		if (IS_ERR(kvm_regs)) {
			r = PTR_ERR(kvm_regs);
A
Avi Kivity 已提交
2585
			goto out;
2586
		}
2587 2588
		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
		kfree(kvm_regs);
A
Avi Kivity 已提交
2589 2590 2591
		break;
	}
	case KVM_GET_SREGS: {
2592 2593 2594 2595 2596
		kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
		r = -ENOMEM;
		if (!kvm_sregs)
			goto out;
		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
A
Avi Kivity 已提交
2597 2598 2599
		if (r)
			goto out;
		r = -EFAULT;
2600
		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
A
Avi Kivity 已提交
2601 2602 2603 2604 2605
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_SREGS: {
2606 2607 2608
		kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
		if (IS_ERR(kvm_sregs)) {
			r = PTR_ERR(kvm_sregs);
G
Guo Chao 已提交
2609
			kvm_sregs = NULL;
A
Avi Kivity 已提交
2610
			goto out;
2611
		}
2612
		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
A
Avi Kivity 已提交
2613 2614
		break;
	}
2615 2616 2617 2618 2619 2620 2621
	case KVM_GET_MP_STATE: {
		struct kvm_mp_state mp_state;

		r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
		if (r)
			goto out;
		r = -EFAULT;
2622
		if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
2623 2624 2625 2626 2627 2628 2629 2630
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_MP_STATE: {
		struct kvm_mp_state mp_state;

		r = -EFAULT;
2631
		if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
2632 2633 2634 2635
			goto out;
		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
		break;
	}
A
Avi Kivity 已提交
2636 2637 2638 2639
	case KVM_TRANSLATE: {
		struct kvm_translation tr;

		r = -EFAULT;
2640
		if (copy_from_user(&tr, argp, sizeof(tr)))
A
Avi Kivity 已提交
2641
			goto out;
2642
		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
A
Avi Kivity 已提交
2643 2644 2645
		if (r)
			goto out;
		r = -EFAULT;
2646
		if (copy_to_user(argp, &tr, sizeof(tr)))
A
Avi Kivity 已提交
2647 2648 2649 2650
			goto out;
		r = 0;
		break;
	}
J
Jan Kiszka 已提交
2651 2652
	case KVM_SET_GUEST_DEBUG: {
		struct kvm_guest_debug dbg;
A
Avi Kivity 已提交
2653 2654

		r = -EFAULT;
2655
		if (copy_from_user(&dbg, argp, sizeof(dbg)))
A
Avi Kivity 已提交
2656
			goto out;
J
Jan Kiszka 已提交
2657
		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
A
Avi Kivity 已提交
2658 2659
		break;
	}
A
Avi Kivity 已提交
2660 2661 2662 2663 2664 2665 2666 2667 2668
	case KVM_SET_SIGNAL_MASK: {
		struct kvm_signal_mask __user *sigmask_arg = argp;
		struct kvm_signal_mask kvm_sigmask;
		sigset_t sigset, *p;

		p = NULL;
		if (argp) {
			r = -EFAULT;
			if (copy_from_user(&kvm_sigmask, argp,
2669
					   sizeof(kvm_sigmask)))
A
Avi Kivity 已提交
2670 2671
				goto out;
			r = -EINVAL;
2672
			if (kvm_sigmask.len != sizeof(sigset))
A
Avi Kivity 已提交
2673 2674 2675
				goto out;
			r = -EFAULT;
			if (copy_from_user(&sigset, sigmask_arg->sigset,
2676
					   sizeof(sigset)))
A
Avi Kivity 已提交
2677 2678 2679
				goto out;
			p = &sigset;
		}
2680
		r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
A
Avi Kivity 已提交
2681 2682
		break;
	}
A
Avi Kivity 已提交
2683
	case KVM_GET_FPU: {
2684 2685 2686 2687 2688
		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
		r = -ENOMEM;
		if (!fpu)
			goto out;
		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
A
Avi Kivity 已提交
2689 2690 2691
		if (r)
			goto out;
		r = -EFAULT;
2692
		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
A
Avi Kivity 已提交
2693 2694 2695 2696 2697
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_FPU: {
2698 2699 2700
		fpu = memdup_user(argp, sizeof(*fpu));
		if (IS_ERR(fpu)) {
			r = PTR_ERR(fpu);
G
Guo Chao 已提交
2701
			fpu = NULL;
A
Avi Kivity 已提交
2702
			goto out;
2703
		}
2704
		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
A
Avi Kivity 已提交
2705 2706
		break;
	}
A
Avi Kivity 已提交
2707
	default:
2708
		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
A
Avi Kivity 已提交
2709 2710
	}
out:
2711
	vcpu_put(vcpu);
2712 2713
	kfree(fpu);
	kfree(kvm_sregs);
A
Avi Kivity 已提交
2714 2715 2716
	return r;
}

2717
#ifdef CONFIG_KVM_COMPAT
2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737
static long kvm_vcpu_compat_ioctl(struct file *filp,
				  unsigned int ioctl, unsigned long arg)
{
	struct kvm_vcpu *vcpu = filp->private_data;
	void __user *argp = compat_ptr(arg);
	int r;

	if (vcpu->kvm->mm != current->mm)
		return -EIO;

	switch (ioctl) {
	case KVM_SET_SIGNAL_MASK: {
		struct kvm_signal_mask __user *sigmask_arg = argp;
		struct kvm_signal_mask kvm_sigmask;
		compat_sigset_t csigset;
		sigset_t sigset;

		if (argp) {
			r = -EFAULT;
			if (copy_from_user(&kvm_sigmask, argp,
2738
					   sizeof(kvm_sigmask)))
2739 2740
				goto out;
			r = -EINVAL;
2741
			if (kvm_sigmask.len != sizeof(csigset))
2742 2743 2744
				goto out;
			r = -EFAULT;
			if (copy_from_user(&csigset, sigmask_arg->sigset,
2745
					   sizeof(csigset)))
2746
				goto out;
2747 2748 2749 2750
			sigset_from_compat(&sigset, &csigset);
			r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
		} else
			r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
		break;
	}
	default:
		r = kvm_vcpu_ioctl(filp, ioctl, arg);
	}

out:
	return r;
}
#endif

S
Scott Wood 已提交
2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808
static int kvm_device_ioctl_attr(struct kvm_device *dev,
				 int (*accessor)(struct kvm_device *dev,
						 struct kvm_device_attr *attr),
				 unsigned long arg)
{
	struct kvm_device_attr attr;

	if (!accessor)
		return -EPERM;

	if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
		return -EFAULT;

	return accessor(dev, &attr);
}

static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
			     unsigned long arg)
{
	struct kvm_device *dev = filp->private_data;

	switch (ioctl) {
	case KVM_SET_DEVICE_ATTR:
		return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
	case KVM_GET_DEVICE_ATTR:
		return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
	case KVM_HAS_DEVICE_ATTR:
		return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
	default:
		if (dev->ops->ioctl)
			return dev->ops->ioctl(dev, ioctl, arg);

		return -ENOTTY;
	}
}

static int kvm_device_release(struct inode *inode, struct file *filp)
{
	struct kvm_device *dev = filp->private_data;
	struct kvm *kvm = dev->kvm;

	kvm_put_kvm(kvm);
	return 0;
}

static const struct file_operations kvm_device_fops = {
	.unlocked_ioctl = kvm_device_ioctl,
2809
#ifdef CONFIG_KVM_COMPAT
2810 2811
	.compat_ioctl = kvm_device_ioctl,
#endif
S
Scott Wood 已提交
2812 2813 2814 2815 2816 2817 2818 2819 2820 2821 2822
	.release = kvm_device_release,
};

struct kvm_device *kvm_device_from_filp(struct file *filp)
{
	if (filp->f_op != &kvm_device_fops)
		return NULL;

	return filp->private_data;
}

2823
static struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
2824
#ifdef CONFIG_KVM_MPIC
2825 2826
	[KVM_DEV_TYPE_FSL_MPIC_20]	= &kvm_mpic_ops,
	[KVM_DEV_TYPE_FSL_MPIC_42]	= &kvm_mpic_ops,
2827
#endif
2828

2829
#ifdef CONFIG_KVM_XICS
2830
	[KVM_DEV_TYPE_XICS]		= &kvm_xics_ops,
A
Alex Williamson 已提交
2831
#endif
2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845
};

int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type)
{
	if (type >= ARRAY_SIZE(kvm_device_ops_table))
		return -ENOSPC;

	if (kvm_device_ops_table[type] != NULL)
		return -EEXIST;

	kvm_device_ops_table[type] = ops;
	return 0;
}

2846 2847 2848 2849 2850 2851
void kvm_unregister_device_ops(u32 type)
{
	if (kvm_device_ops_table[type] != NULL)
		kvm_device_ops_table[type] = NULL;
}

S
Scott Wood 已提交
2852 2853 2854 2855 2856 2857 2858 2859
static int kvm_ioctl_create_device(struct kvm *kvm,
				   struct kvm_create_device *cd)
{
	struct kvm_device_ops *ops = NULL;
	struct kvm_device *dev;
	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
	int ret;

2860 2861 2862 2863 2864
	if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
		return -ENODEV;

	ops = kvm_device_ops_table[cd->type];
	if (ops == NULL)
S
Scott Wood 已提交
2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876
		return -ENODEV;

	if (test)
		return 0;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return -ENOMEM;

	dev->ops = ops;
	dev->kvm = kvm;

2877
	mutex_lock(&kvm->lock);
S
Scott Wood 已提交
2878 2879
	ret = ops->create(dev, cd->type);
	if (ret < 0) {
2880
		mutex_unlock(&kvm->lock);
S
Scott Wood 已提交
2881 2882 2883
		kfree(dev);
		return ret;
	}
2884 2885
	list_add(&dev->vm_node, &kvm->devices);
	mutex_unlock(&kvm->lock);
S
Scott Wood 已提交
2886

2887 2888 2889
	if (ops->init)
		ops->init(dev);

2890
	ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
S
Scott Wood 已提交
2891 2892
	if (ret < 0) {
		ops->destroy(dev);
2893 2894 2895
		mutex_lock(&kvm->lock);
		list_del(&dev->vm_node);
		mutex_unlock(&kvm->lock);
S
Scott Wood 已提交
2896 2897 2898 2899 2900 2901 2902 2903
		return ret;
	}

	kvm_get_kvm(kvm);
	cd->fd = ret;
	return 0;
}

2904 2905 2906 2907 2908 2909 2910 2911 2912 2913
static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
{
	switch (arg) {
	case KVM_CAP_USER_MEMORY:
	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
	case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
	case KVM_CAP_INTERNAL_ERROR_DATA:
#ifdef CONFIG_HAVE_KVM_MSI
	case KVM_CAP_SIGNAL_MSI:
#endif
2914
#ifdef CONFIG_HAVE_KVM_IRQFD
2915
	case KVM_CAP_IRQFD:
2916 2917
	case KVM_CAP_IRQFD_RESAMPLE:
#endif
2918
	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
2919 2920 2921 2922 2923
	case KVM_CAP_CHECK_EXTENSION_VM:
		return 1;
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
	case KVM_CAP_IRQ_ROUTING:
		return KVM_MAX_IRQ_ROUTES;
2924 2925 2926 2927
#endif
#if KVM_ADDRESS_SPACE_NUM > 1
	case KVM_CAP_MULTI_ADDRESS_SPACE:
		return KVM_ADDRESS_SPACE_NUM;
2928
#endif
G
Greg Kurz 已提交
2929 2930
	case KVM_CAP_MAX_VCPU_ID:
		return KVM_MAX_VCPU_ID;
2931 2932 2933 2934 2935 2936
	default:
		break;
	}
	return kvm_vm_ioctl_check_extension(kvm, arg);
}

A
Avi Kivity 已提交
2937 2938 2939 2940 2941
static long kvm_vm_ioctl(struct file *filp,
			   unsigned int ioctl, unsigned long arg)
{
	struct kvm *kvm = filp->private_data;
	void __user *argp = (void __user *)arg;
2942
	int r;
A
Avi Kivity 已提交
2943

2944 2945
	if (kvm->mm != current->mm)
		return -EIO;
A
Avi Kivity 已提交
2946 2947 2948 2949
	switch (ioctl) {
	case KVM_CREATE_VCPU:
		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
		break;
2950 2951 2952 2953 2954
	case KVM_SET_USER_MEMORY_REGION: {
		struct kvm_userspace_memory_region kvm_userspace_mem;

		r = -EFAULT;
		if (copy_from_user(&kvm_userspace_mem, argp,
2955
						sizeof(kvm_userspace_mem)))
2956 2957
			goto out;

2958
		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
A
Avi Kivity 已提交
2959 2960 2961 2962 2963 2964
		break;
	}
	case KVM_GET_DIRTY_LOG: {
		struct kvm_dirty_log log;

		r = -EFAULT;
2965
		if (copy_from_user(&log, argp, sizeof(log)))
A
Avi Kivity 已提交
2966
			goto out;
2967
		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
A
Avi Kivity 已提交
2968 2969
		break;
	}
2970 2971 2972
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
	case KVM_REGISTER_COALESCED_MMIO: {
		struct kvm_coalesced_mmio_zone zone;
2973

2974
		r = -EFAULT;
2975
		if (copy_from_user(&zone, argp, sizeof(zone)))
2976 2977 2978 2979 2980 2981
			goto out;
		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
		break;
	}
	case KVM_UNREGISTER_COALESCED_MMIO: {
		struct kvm_coalesced_mmio_zone zone;
2982

2983
		r = -EFAULT;
2984
		if (copy_from_user(&zone, argp, sizeof(zone)))
2985 2986 2987 2988 2989
			goto out;
		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
		break;
	}
#endif
G
Gregory Haskins 已提交
2990 2991 2992 2993
	case KVM_IRQFD: {
		struct kvm_irqfd data;

		r = -EFAULT;
2994
		if (copy_from_user(&data, argp, sizeof(data)))
G
Gregory Haskins 已提交
2995
			goto out;
2996
		r = kvm_irqfd(kvm, &data);
G
Gregory Haskins 已提交
2997 2998
		break;
	}
G
Gregory Haskins 已提交
2999 3000 3001 3002
	case KVM_IOEVENTFD: {
		struct kvm_ioeventfd data;

		r = -EFAULT;
3003
		if (copy_from_user(&data, argp, sizeof(data)))
G
Gregory Haskins 已提交
3004 3005 3006 3007
			goto out;
		r = kvm_ioeventfd(kvm, &data);
		break;
	}
3008 3009 3010 3011 3012
#ifdef CONFIG_HAVE_KVM_MSI
	case KVM_SIGNAL_MSI: {
		struct kvm_msi msi;

		r = -EFAULT;
3013
		if (copy_from_user(&msi, argp, sizeof(msi)))
3014 3015 3016 3017
			goto out;
		r = kvm_send_userspace_msi(kvm, &msi);
		break;
	}
3018 3019 3020 3021 3022 3023 3024
#endif
#ifdef __KVM_HAVE_IRQ_LINE
	case KVM_IRQ_LINE_STATUS:
	case KVM_IRQ_LINE: {
		struct kvm_irq_level irq_event;

		r = -EFAULT;
3025
		if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
3026 3027
			goto out;

3028 3029
		r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
					ioctl == KVM_IRQ_LINE_STATUS);
3030 3031 3032 3033 3034
		if (r)
			goto out;

		r = -EFAULT;
		if (ioctl == KVM_IRQ_LINE_STATUS) {
3035
			if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
3036 3037 3038 3039 3040 3041
				goto out;
		}

		r = 0;
		break;
	}
3042
#endif
3043 3044 3045 3046
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
	case KVM_SET_GSI_ROUTING: {
		struct kvm_irq_routing routing;
		struct kvm_irq_routing __user *urouting;
3047
		struct kvm_irq_routing_entry *entries = NULL;
3048 3049 3050 3051 3052

		r = -EFAULT;
		if (copy_from_user(&routing, argp, sizeof(routing)))
			goto out;
		r = -EINVAL;
3053
		if (routing.nr > KVM_MAX_IRQ_ROUTES)
3054 3055 3056
			goto out;
		if (routing.flags)
			goto out;
3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067
		if (routing.nr) {
			r = -ENOMEM;
			entries = vmalloc(routing.nr * sizeof(*entries));
			if (!entries)
				goto out;
			r = -EFAULT;
			urouting = argp;
			if (copy_from_user(entries, urouting->entries,
					   routing.nr * sizeof(*entries)))
				goto out_free_irq_routing;
		}
3068 3069
		r = kvm_set_irq_routing(kvm, entries, routing.nr,
					routing.flags);
3070
out_free_irq_routing:
3071 3072 3073 3074
		vfree(entries);
		break;
	}
#endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
S
Scott Wood 已提交
3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092
	case KVM_CREATE_DEVICE: {
		struct kvm_create_device cd;

		r = -EFAULT;
		if (copy_from_user(&cd, argp, sizeof(cd)))
			goto out;

		r = kvm_ioctl_create_device(kvm, &cd);
		if (r)
			goto out;

		r = -EFAULT;
		if (copy_to_user(argp, &cd, sizeof(cd)))
			goto out;

		r = 0;
		break;
	}
3093 3094 3095
	case KVM_CHECK_EXTENSION:
		r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
		break;
3096
	default:
3097
		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
3098 3099 3100 3101 3102
	}
out:
	return r;
}

3103
#ifdef CONFIG_KVM_COMPAT
3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146
struct compat_kvm_dirty_log {
	__u32 slot;
	__u32 padding1;
	union {
		compat_uptr_t dirty_bitmap; /* one bit per page */
		__u64 padding2;
	};
};

static long kvm_vm_compat_ioctl(struct file *filp,
			   unsigned int ioctl, unsigned long arg)
{
	struct kvm *kvm = filp->private_data;
	int r;

	if (kvm->mm != current->mm)
		return -EIO;
	switch (ioctl) {
	case KVM_GET_DIRTY_LOG: {
		struct compat_kvm_dirty_log compat_log;
		struct kvm_dirty_log log;

		r = -EFAULT;
		if (copy_from_user(&compat_log, (void __user *)arg,
				   sizeof(compat_log)))
			goto out;
		log.slot	 = compat_log.slot;
		log.padding1	 = compat_log.padding1;
		log.padding2	 = compat_log.padding2;
		log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);

		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
		break;
	}
	default:
		r = kvm_vm_ioctl(filp, ioctl, arg);
	}

out:
	return r;
}
#endif

3147
static struct file_operations kvm_vm_fops = {
3148 3149
	.release        = kvm_vm_release,
	.unlocked_ioctl = kvm_vm_ioctl,
3150
#ifdef CONFIG_KVM_COMPAT
3151 3152
	.compat_ioctl   = kvm_vm_compat_ioctl,
#endif
3153
	.llseek		= noop_llseek,
3154 3155
};

3156
static int kvm_dev_ioctl_create_vm(unsigned long type)
3157
{
3158
	int r;
3159
	struct kvm *kvm;
3160
	struct file *file;
3161

3162
	kvm = kvm_create_vm(type);
3163 3164
	if (IS_ERR(kvm))
		return PTR_ERR(kvm);
3165 3166 3167 3168 3169 3170 3171
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
	r = kvm_coalesced_mmio_init(kvm);
	if (r < 0) {
		kvm_put_kvm(kvm);
		return r;
	}
#endif
3172
	r = get_unused_fd_flags(O_CLOEXEC);
3173
	if (r < 0) {
A
Al Viro 已提交
3174
		kvm_put_kvm(kvm);
3175 3176
		return r;
	}
3177 3178 3179 3180 3181 3182
	file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
	if (IS_ERR(file)) {
		put_unused_fd(r);
		kvm_put_kvm(kvm);
		return PTR_ERR(file);
	}
3183 3184

	if (kvm_create_vm_debugfs(kvm, r) < 0) {
3185 3186
		put_unused_fd(r);
		fput(file);
3187 3188
		return -ENOMEM;
	}
3189

3190
	fd_install(r, file);
3191
	return r;
3192 3193 3194 3195 3196
}

static long kvm_dev_ioctl(struct file *filp,
			  unsigned int ioctl, unsigned long arg)
{
3197
	long r = -EINVAL;
3198 3199 3200

	switch (ioctl) {
	case KVM_GET_API_VERSION:
3201 3202
		if (arg)
			goto out;
3203 3204 3205
		r = KVM_API_VERSION;
		break;
	case KVM_CREATE_VM:
3206
		r = kvm_dev_ioctl_create_vm(arg);
3207
		break;
3208
	case KVM_CHECK_EXTENSION:
3209
		r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
3210
		break;
3211 3212 3213
	case KVM_GET_VCPU_MMAP_SIZE:
		if (arg)
			goto out;
3214 3215 3216
		r = PAGE_SIZE;     /* struct kvm_run */
#ifdef CONFIG_X86
		r += PAGE_SIZE;    /* pio data page */
3217 3218 3219
#endif
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
		r += PAGE_SIZE;    /* coalesced mmio ring page */
3220
#endif
3221
		break;
3222 3223 3224
	case KVM_TRACE_ENABLE:
	case KVM_TRACE_PAUSE:
	case KVM_TRACE_DISABLE:
3225
		r = -EOPNOTSUPP;
3226
		break;
A
Avi Kivity 已提交
3227
	default:
3228
		return kvm_arch_dev_ioctl(filp, ioctl, arg);
A
Avi Kivity 已提交
3229 3230 3231 3232 3233 3234 3235 3236
	}
out:
	return r;
}

static struct file_operations kvm_chardev_ops = {
	.unlocked_ioctl = kvm_dev_ioctl,
	.compat_ioctl   = kvm_dev_ioctl,
3237
	.llseek		= noop_llseek,
A
Avi Kivity 已提交
3238 3239 3240
};

static struct miscdevice kvm_dev = {
A
Avi Kivity 已提交
3241
	KVM_MINOR,
A
Avi Kivity 已提交
3242 3243 3244 3245
	"kvm",
	&kvm_chardev_ops,
};

3246
static void hardware_enable_nolock(void *junk)
3247 3248
{
	int cpu = raw_smp_processor_id();
3249
	int r;
3250

3251
	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
3252
		return;
3253

3254
	cpumask_set_cpu(cpu, cpus_hardware_enabled);
3255

3256
	r = kvm_arch_hardware_enable();
3257 3258 3259 3260

	if (r) {
		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
		atomic_inc(&hardware_enable_failed);
X
Xiubo Li 已提交
3261
		pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
3262
	}
3263 3264
}

3265
static int kvm_starting_cpu(unsigned int cpu)
3266
{
3267
	raw_spin_lock(&kvm_count_lock);
3268 3269
	if (kvm_usage_count)
		hardware_enable_nolock(NULL);
3270
	raw_spin_unlock(&kvm_count_lock);
3271
	return 0;
3272 3273 3274
}

static void hardware_disable_nolock(void *junk)
3275 3276 3277
{
	int cpu = raw_smp_processor_id();

3278
	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
3279
		return;
3280
	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3281
	kvm_arch_hardware_disable();
3282 3283
}

3284
static int kvm_dying_cpu(unsigned int cpu)
3285
{
3286
	raw_spin_lock(&kvm_count_lock);
3287 3288
	if (kvm_usage_count)
		hardware_disable_nolock(NULL);
3289
	raw_spin_unlock(&kvm_count_lock);
3290
	return 0;
3291 3292
}

3293 3294 3295 3296 3297 3298
static void hardware_disable_all_nolock(void)
{
	BUG_ON(!kvm_usage_count);

	kvm_usage_count--;
	if (!kvm_usage_count)
3299
		on_each_cpu(hardware_disable_nolock, NULL, 1);
3300 3301 3302 3303
}

static void hardware_disable_all(void)
{
3304
	raw_spin_lock(&kvm_count_lock);
3305
	hardware_disable_all_nolock();
3306
	raw_spin_unlock(&kvm_count_lock);
3307 3308 3309 3310 3311 3312
}

static int hardware_enable_all(void)
{
	int r = 0;

3313
	raw_spin_lock(&kvm_count_lock);
3314 3315 3316 3317

	kvm_usage_count++;
	if (kvm_usage_count == 1) {
		atomic_set(&hardware_enable_failed, 0);
3318
		on_each_cpu(hardware_enable_nolock, NULL, 1);
3319 3320 3321 3322 3323 3324 3325

		if (atomic_read(&hardware_enable_failed)) {
			hardware_disable_all_nolock();
			r = -EBUSY;
		}
	}

3326
	raw_spin_unlock(&kvm_count_lock);
3327 3328 3329 3330

	return r;
}

3331
static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
M
Mike Day 已提交
3332
		      void *v)
3333
{
3334 3335 3336 3337 3338 3339
	/*
	 * Some (well, at least mine) BIOSes hang on reboot if
	 * in vmx root mode.
	 *
	 * And Intel TXT required VMX off for all cpu when system shutdown.
	 */
X
Xiubo Li 已提交
3340
	pr_info("kvm: exiting hardware virtualization\n");
3341
	kvm_rebooting = true;
3342
	on_each_cpu(hardware_disable_nolock, NULL, 1);
3343 3344 3345 3346 3347 3348 3349 3350
	return NOTIFY_OK;
}

static struct notifier_block kvm_reboot_notifier = {
	.notifier_call = kvm_reboot,
	.priority = 0,
};

M
Marcelo Tosatti 已提交
3351
static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
3352 3353 3354 3355
{
	int i;

	for (i = 0; i < bus->dev_count; i++) {
3356
		struct kvm_io_device *pos = bus->range[i].dev;
3357 3358 3359

		kvm_iodevice_destructor(pos);
	}
M
Marcelo Tosatti 已提交
3360
	kfree(bus);
3361 3362
}

3363
static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
X
Xiubo Li 已提交
3364
				 const struct kvm_io_range *r2)
3365
{
J
Jason Wang 已提交
3366 3367 3368 3369
	gpa_t addr1 = r1->addr;
	gpa_t addr2 = r2->addr;

	if (addr1 < addr2)
3370
		return -1;
J
Jason Wang 已提交
3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382

	/* If r2->len == 0, match the exact address.  If r2->len != 0,
	 * accept any overlapping write.  Any order is acceptable for
	 * overlapping ranges, because kvm_io_bus_get_first_dev ensures
	 * we process all of them.
	 */
	if (r2->len) {
		addr1 += r1->len;
		addr2 += r2->len;
	}

	if (addr1 > addr2)
3383
		return 1;
J
Jason Wang 已提交
3384

3385 3386 3387
	return 0;
}

3388 3389
static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
{
3390
	return kvm_io_bus_cmp(p1, p2);
3391 3392
}

G
Geoff Levand 已提交
3393
static int kvm_io_bus_insert_dev(struct kvm_io_bus *bus, struct kvm_io_device *dev,
3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407
			  gpa_t addr, int len)
{
	bus->range[bus->dev_count++] = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
		.dev = dev,
	};

	sort(bus->range, bus->dev_count, sizeof(struct kvm_io_range),
		kvm_io_bus_sort_cmp, NULL);

	return 0;
}

G
Geoff Levand 已提交
3408
static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425
			     gpa_t addr, int len)
{
	struct kvm_io_range *range, key;
	int off;

	key = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};

	range = bsearch(&key, bus->range, bus->dev_count,
			sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
	if (range == NULL)
		return -ENOENT;

	off = range - bus->range;

3426
	while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
3427 3428 3429 3430 3431
		off--;

	return off;
}

3432
static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
C
Cornelia Huck 已提交
3433 3434 3435 3436 3437 3438 3439 3440 3441
			      struct kvm_io_range *range, const void *val)
{
	int idx;

	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
	if (idx < 0)
		return -EOPNOTSUPP;

	while (idx < bus->dev_count &&
3442
		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3443
		if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
C
Cornelia Huck 已提交
3444 3445 3446 3447 3448 3449 3450 3451
					range->len, val))
			return idx;
		idx++;
	}

	return -EOPNOTSUPP;
}

3452
/* kvm_io_bus_write - called under kvm->slots_lock */
3453
int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3454
		     int len, const void *val)
3455
{
3456
	struct kvm_io_bus *bus;
3457
	struct kvm_io_range range;
C
Cornelia Huck 已提交
3458
	int r;
3459 3460 3461 3462 3463

	range = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};
3464

3465 3466
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
	r = __kvm_io_bus_write(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3467 3468 3469 3470
	return r < 0 ? r : 0;
}

/* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3471 3472
int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
			    gpa_t addr, int len, const void *val, long cookie)
C
Cornelia Huck 已提交
3473 3474 3475 3476 3477 3478 3479 3480 3481
{
	struct kvm_io_bus *bus;
	struct kvm_io_range range;

	range = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};

3482
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
C
Cornelia Huck 已提交
3483 3484 3485

	/* First try the device referenced by cookie. */
	if ((cookie >= 0) && (cookie < bus->dev_count) &&
3486
	    (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
3487
		if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
C
Cornelia Huck 已提交
3488 3489 3490 3491 3492 3493 3494
					val))
			return cookie;

	/*
	 * cookie contained garbage; fall back to search and return the
	 * correct cookie value.
	 */
3495
	return __kvm_io_bus_write(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3496 3497
}

3498 3499
static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
			     struct kvm_io_range *range, void *val)
C
Cornelia Huck 已提交
3500 3501 3502 3503
{
	int idx;

	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3504 3505 3506 3507
	if (idx < 0)
		return -EOPNOTSUPP;

	while (idx < bus->dev_count &&
3508
		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3509
		if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
C
Cornelia Huck 已提交
3510 3511
				       range->len, val))
			return idx;
3512 3513 3514
		idx++;
	}

3515 3516
	return -EOPNOTSUPP;
}
3517
EXPORT_SYMBOL_GPL(kvm_io_bus_write);
3518

3519
/* kvm_io_bus_read - called under kvm->slots_lock */
3520
int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
M
Marcelo Tosatti 已提交
3521
		    int len, void *val)
3522
{
3523
	struct kvm_io_bus *bus;
3524
	struct kvm_io_range range;
C
Cornelia Huck 已提交
3525
	int r;
3526 3527 3528 3529 3530

	range = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};
M
Marcelo Tosatti 已提交
3531

3532 3533
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
	r = __kvm_io_bus_read(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3534 3535
	return r < 0 ? r : 0;
}
3536

3537

3538
/* Caller must hold slots_lock. */
3539 3540
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
			    int len, struct kvm_io_device *dev)
3541
{
M
Marcelo Tosatti 已提交
3542
	struct kvm_io_bus *new_bus, *bus;
3543

M
Marcelo Tosatti 已提交
3544
	bus = kvm->buses[bus_idx];
3545 3546
	/* exclude ioeventfd which is limited by maximum fd */
	if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3547
		return -ENOSPC;
3548

3549
	new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count + 1) *
3550
			  sizeof(struct kvm_io_range)), GFP_KERNEL);
M
Marcelo Tosatti 已提交
3551 3552
	if (!new_bus)
		return -ENOMEM;
3553 3554
	memcpy(new_bus, bus, sizeof(*bus) + (bus->dev_count *
	       sizeof(struct kvm_io_range)));
3555
	kvm_io_bus_insert_dev(new_bus, dev, addr, len);
M
Marcelo Tosatti 已提交
3556 3557 3558
	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
	synchronize_srcu_expedited(&kvm->srcu);
	kfree(bus);
3559 3560 3561 3562

	return 0;
}

3563
/* Caller must hold slots_lock. */
M
Marcelo Tosatti 已提交
3564 3565
int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
			      struct kvm_io_device *dev)
3566
{
M
Marcelo Tosatti 已提交
3567 3568
	int i, r;
	struct kvm_io_bus *new_bus, *bus;
3569

3570
	bus = kvm->buses[bus_idx];
M
Marcelo Tosatti 已提交
3571
	r = -ENOENT;
3572 3573
	for (i = 0; i < bus->dev_count; i++)
		if (bus->range[i].dev == dev) {
M
Marcelo Tosatti 已提交
3574
			r = 0;
3575 3576
			break;
		}
M
Marcelo Tosatti 已提交
3577

3578
	if (r)
M
Marcelo Tosatti 已提交
3579
		return r;
3580

3581
	new_bus = kmalloc(sizeof(*bus) + ((bus->dev_count - 1) *
3582 3583 3584 3585 3586 3587 3588 3589
			  sizeof(struct kvm_io_range)), GFP_KERNEL);
	if (!new_bus)
		return -ENOMEM;

	memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
	new_bus->dev_count--;
	memcpy(new_bus->range + i, bus->range + i + 1,
	       (new_bus->dev_count - i) * sizeof(struct kvm_io_range));
M
Marcelo Tosatti 已提交
3590 3591 3592 3593 3594

	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
	synchronize_srcu_expedited(&kvm->srcu);
	kfree(bus);
	return r;
3595 3596
}

3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620
struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
					 gpa_t addr)
{
	struct kvm_io_bus *bus;
	int dev_idx, srcu_idx;
	struct kvm_io_device *iodev = NULL;

	srcu_idx = srcu_read_lock(&kvm->srcu);

	bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);

	dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1);
	if (dev_idx < 0)
		goto out_unlock;

	iodev = bus->range[dev_idx].dev;

out_unlock:
	srcu_read_unlock(&kvm->srcu, srcu_idx);

	return iodev;
}
EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev);

3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658
static int kvm_debugfs_open(struct inode *inode, struct file *file,
			   int (*get)(void *, u64 *), int (*set)(void *, u64),
			   const char *fmt)
{
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
					  inode->i_private;

	/* The debugfs files are a reference to the kvm struct which
	 * is still valid when kvm_destroy_vm is called.
	 * To avoid the race between open and the removal of the debugfs
	 * directory we test against the users count.
	 */
	if (!atomic_add_unless(&stat_data->kvm->users_count, 1, 0))
		return -ENOENT;

	if (simple_attr_open(inode, file, get, set, fmt)) {
		kvm_put_kvm(stat_data->kvm);
		return -ENOMEM;
	}

	return 0;
}

static int kvm_debugfs_release(struct inode *inode, struct file *file)
{
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
					  inode->i_private;

	simple_attr_release(inode, file);
	kvm_put_kvm(stat_data->kvm);

	return 0;
}

static int vm_stat_get_per_vm(void *data, u64 *val)
{
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;

3659
	*val = *(ulong *)((void *)stat_data->kvm + stat_data->offset);
3660 3661 3662 3663

	return 0;
}

3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675
static int vm_stat_clear_per_vm(void *data, u64 val)
{
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;

	if (val)
		return -EINVAL;

	*(ulong *)((void *)stat_data->kvm + stat_data->offset) = 0;

	return 0;
}

3676 3677 3678 3679
static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
{
	__simple_attr_check_format("%llu\n", 0ull);
	return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
3680
				vm_stat_clear_per_vm, "%llu\n");
3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700
}

static const struct file_operations vm_stat_get_per_vm_fops = {
	.owner   = THIS_MODULE,
	.open    = vm_stat_get_per_vm_open,
	.release = kvm_debugfs_release,
	.read    = simple_attr_read,
	.write   = simple_attr_write,
	.llseek  = generic_file_llseek,
};

static int vcpu_stat_get_per_vm(void *data, u64 *val)
{
	int i;
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
	struct kvm_vcpu *vcpu;

	*val = 0;

	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
3701
		*val += *(u64 *)((void *)vcpu + stat_data->offset);
3702 3703 3704 3705

	return 0;
}

3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720
static int vcpu_stat_clear_per_vm(void *data, u64 val)
{
	int i;
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
	struct kvm_vcpu *vcpu;

	if (val)
		return -EINVAL;

	kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
		*(u64 *)((void *)vcpu + stat_data->offset) = 0;

	return 0;
}

3721 3722 3723 3724
static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
{
	__simple_attr_check_format("%llu\n", 0ull);
	return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
3725
				 vcpu_stat_clear_per_vm, "%llu\n");
3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741
}

static const struct file_operations vcpu_stat_get_per_vm_fops = {
	.owner   = THIS_MODULE,
	.open    = vcpu_stat_get_per_vm_open,
	.release = kvm_debugfs_release,
	.read    = simple_attr_read,
	.write   = simple_attr_write,
	.llseek  = generic_file_llseek,
};

static const struct file_operations *stat_fops_per_vm[] = {
	[KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
	[KVM_STAT_VM]   = &vm_stat_get_per_vm_fops,
};

3742
static int vm_stat_get(void *_offset, u64 *val)
3743 3744 3745
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
3746 3747
	struct kvm_stat_data stat_tmp = {.offset = offset};
	u64 tmp_val;
3748

3749
	*val = 0;
3750
	spin_lock(&kvm_lock);
3751 3752 3753 3754 3755
	list_for_each_entry(kvm, &vm_list, vm_list) {
		stat_tmp.kvm = kvm;
		vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
		*val += tmp_val;
	}
3756
	spin_unlock(&kvm_lock);
3757
	return 0;
3758 3759
}

3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779
static int vm_stat_clear(void *_offset, u64 val)
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
	struct kvm_stat_data stat_tmp = {.offset = offset};

	if (val)
		return -EINVAL;

	spin_lock(&kvm_lock);
	list_for_each_entry(kvm, &vm_list, vm_list) {
		stat_tmp.kvm = kvm;
		vm_stat_clear_per_vm((void *)&stat_tmp, 0);
	}
	spin_unlock(&kvm_lock);

	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, vm_stat_clear, "%llu\n");
3780

3781
static int vcpu_stat_get(void *_offset, u64 *val)
A
Avi Kivity 已提交
3782 3783 3784
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
3785 3786
	struct kvm_stat_data stat_tmp = {.offset = offset};
	u64 tmp_val;
A
Avi Kivity 已提交
3787

3788
	*val = 0;
3789
	spin_lock(&kvm_lock);
3790 3791 3792 3793 3794
	list_for_each_entry(kvm, &vm_list, vm_list) {
		stat_tmp.kvm = kvm;
		vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
		*val += tmp_val;
	}
3795
	spin_unlock(&kvm_lock);
3796
	return 0;
A
Avi Kivity 已提交
3797 3798
}

3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819
static int vcpu_stat_clear(void *_offset, u64 val)
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
	struct kvm_stat_data stat_tmp = {.offset = offset};

	if (val)
		return -EINVAL;

	spin_lock(&kvm_lock);
	list_for_each_entry(kvm, &vm_list, vm_list) {
		stat_tmp.kvm = kvm;
		vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
	}
	spin_unlock(&kvm_lock);

	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, vcpu_stat_clear,
			"%llu\n");
3820

3821
static const struct file_operations *stat_fops[] = {
3822 3823 3824
	[KVM_STAT_VCPU] = &vcpu_stat_fops,
	[KVM_STAT_VM]   = &vm_stat_fops,
};
A
Avi Kivity 已提交
3825

3826
static int kvm_init_debug(void)
A
Avi Kivity 已提交
3827
{
3828
	int r = -EEXIST;
A
Avi Kivity 已提交
3829 3830
	struct kvm_stats_debugfs_item *p;

3831
	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
3832 3833 3834
	if (kvm_debugfs_dir == NULL)
		goto out;

3835 3836
	kvm_debugfs_num_entries = 0;
	for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
3837
		if (!debugfs_create_file(p->name, 0644, kvm_debugfs_dir,
3838 3839
					 (void *)(long)p->offset,
					 stat_fops[p->kind]))
3840 3841 3842 3843 3844 3845 3846 3847 3848
			goto out_dir;
	}

	return 0;

out_dir:
	debugfs_remove_recursive(kvm_debugfs_dir);
out:
	return r;
A
Avi Kivity 已提交
3849 3850
}

3851
static int kvm_suspend(void)
3852
{
3853
	if (kvm_usage_count)
3854
		hardware_disable_nolock(NULL);
3855 3856 3857
	return 0;
}

3858
static void kvm_resume(void)
3859
{
3860
	if (kvm_usage_count) {
3861
		WARN_ON(raw_spin_is_locked(&kvm_count_lock));
3862
		hardware_enable_nolock(NULL);
3863
	}
3864 3865
}

3866
static struct syscore_ops kvm_syscore_ops = {
3867 3868 3869 3870
	.suspend = kvm_suspend,
	.resume = kvm_resume,
};

3871 3872 3873 3874 3875 3876 3877 3878 3879
static inline
struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
{
	return container_of(pn, struct kvm_vcpu, preempt_notifier);
}

static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
{
	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
3880

3881 3882
	if (vcpu->preempted)
		vcpu->preempted = false;
3883

R
Radim Krčmář 已提交
3884 3885
	kvm_arch_sched_in(vcpu, cpu);

3886
	kvm_arch_vcpu_load(vcpu, cpu);
3887 3888 3889 3890 3891 3892 3893
}

static void kvm_sched_out(struct preempt_notifier *pn,
			  struct task_struct *next)
{
	struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);

3894 3895
	if (current->state == TASK_RUNNING)
		vcpu->preempted = true;
3896
	kvm_arch_vcpu_put(vcpu);
3897 3898
}

3899
int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
3900
		  struct module *module)
A
Avi Kivity 已提交
3901 3902
{
	int r;
Y
Yang, Sheng 已提交
3903
	int cpu;
A
Avi Kivity 已提交
3904

3905 3906
	r = kvm_arch_init(opaque);
	if (r)
3907
		goto out_fail;
3908

3909 3910 3911 3912
	/*
	 * kvm_arch_init makes sure there's at most one caller
	 * for architectures that support multiple implementations,
	 * like intel and amd on x86.
P
Paolo Bonzini 已提交
3913 3914
	 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
	 * conflicts in case kvm is already setup for another implementation.
3915
	 */
P
Paolo Bonzini 已提交
3916 3917 3918
	r = kvm_irqfd_init();
	if (r)
		goto out_irqfd;
3919

3920
	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
3921 3922 3923 3924
		r = -ENOMEM;
		goto out_free_0;
	}

3925
	r = kvm_arch_hardware_setup();
A
Avi Kivity 已提交
3926
	if (r < 0)
3927
		goto out_free_0a;
A
Avi Kivity 已提交
3928

Y
Yang, Sheng 已提交
3929 3930
	for_each_online_cpu(cpu) {
		smp_call_function_single(cpu,
3931
				kvm_arch_check_processor_compat,
3932
				&r, 1);
Y
Yang, Sheng 已提交
3933
		if (r < 0)
3934
			goto out_free_1;
Y
Yang, Sheng 已提交
3935 3936
	}

3937 3938
	r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "AP_KVM_STARTING",
				      kvm_starting_cpu, kvm_dying_cpu);
A
Avi Kivity 已提交
3939
	if (r)
3940
		goto out_free_2;
A
Avi Kivity 已提交
3941 3942
	register_reboot_notifier(&kvm_reboot_notifier);

3943
	/* A kmem cache lets us meet the alignment requirements of fx_save. */
3944 3945 3946
	if (!vcpu_align)
		vcpu_align = __alignof__(struct kvm_vcpu);
	kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
J
Joe Perches 已提交
3947
					   0, NULL);
3948 3949
	if (!kvm_vcpu_cache) {
		r = -ENOMEM;
3950
		goto out_free_3;
3951 3952
	}

3953 3954 3955 3956
	r = kvm_async_pf_init();
	if (r)
		goto out_free;

A
Avi Kivity 已提交
3957
	kvm_chardev_ops.owner = module;
3958 3959
	kvm_vm_fops.owner = module;
	kvm_vcpu_fops.owner = module;
A
Avi Kivity 已提交
3960 3961 3962

	r = misc_register(&kvm_dev);
	if (r) {
X
Xiubo Li 已提交
3963
		pr_err("kvm: misc device register failed\n");
3964
		goto out_unreg;
A
Avi Kivity 已提交
3965 3966
	}

3967 3968
	register_syscore_ops(&kvm_syscore_ops);

3969 3970 3971
	kvm_preempt_ops.sched_in = kvm_sched_in;
	kvm_preempt_ops.sched_out = kvm_sched_out;

3972 3973
	r = kvm_init_debug();
	if (r) {
X
Xiubo Li 已提交
3974
		pr_err("kvm: create debugfs files failed\n");
3975 3976
		goto out_undebugfs;
	}
3977

P
Paolo Bonzini 已提交
3978 3979 3980
	r = kvm_vfio_ops_init();
	WARN_ON(r);

3981
	return 0;
A
Avi Kivity 已提交
3982

3983 3984
out_undebugfs:
	unregister_syscore_ops(&kvm_syscore_ops);
3985
	misc_deregister(&kvm_dev);
3986 3987
out_unreg:
	kvm_async_pf_deinit();
A
Avi Kivity 已提交
3988
out_free:
3989
	kmem_cache_destroy(kvm_vcpu_cache);
3990
out_free_3:
A
Avi Kivity 已提交
3991
	unregister_reboot_notifier(&kvm_reboot_notifier);
3992
	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
3993 3994
out_free_2:
out_free_1:
3995
	kvm_arch_hardware_unsetup();
3996 3997
out_free_0a:
	free_cpumask_var(cpus_hardware_enabled);
3998
out_free_0:
3999
	kvm_irqfd_exit();
P
Paolo Bonzini 已提交
4000
out_irqfd:
4001 4002
	kvm_arch_exit();
out_fail:
A
Avi Kivity 已提交
4003 4004
	return r;
}
4005
EXPORT_SYMBOL_GPL(kvm_init);
A
Avi Kivity 已提交
4006

4007
void kvm_exit(void)
A
Avi Kivity 已提交
4008
{
4009
	debugfs_remove_recursive(kvm_debugfs_dir);
A
Avi Kivity 已提交
4010
	misc_deregister(&kvm_dev);
4011
	kmem_cache_destroy(kvm_vcpu_cache);
4012
	kvm_async_pf_deinit();
4013
	unregister_syscore_ops(&kvm_syscore_ops);
A
Avi Kivity 已提交
4014
	unregister_reboot_notifier(&kvm_reboot_notifier);
4015
	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
4016
	on_each_cpu(hardware_disable_nolock, NULL, 1);
4017
	kvm_arch_hardware_unsetup();
4018
	kvm_arch_exit();
4019
	kvm_irqfd_exit();
4020
	free_cpumask_var(cpus_hardware_enabled);
4021
	kvm_vfio_ops_exit();
A
Avi Kivity 已提交
4022
}
4023
EXPORT_SYMBOL_GPL(kvm_exit);