kvm_main.c 109.0 KB
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// SPDX-License-Identifier: GPL-2.0-only
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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>
 */

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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/signal.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/stat.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 <linux/io.h>
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#include <linux/lockdep.h>
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#include <linux/kthread.h>
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#include <asm/processor.h>
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#include <asm/ioctl.h>
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#include <linux/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 */
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unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
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module_param(halt_poll_ns, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns);
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/* Default doubles per-vcpu halt_poll_ns. */
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unsigned int halt_poll_ns_grow = 2;
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module_param(halt_poll_ns_grow, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns_grow);
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/* The start value to grow halt_poll_ns from */
unsigned int halt_poll_ns_grow_start = 10000; /* 10us */
module_param(halt_poll_ns_grow_start, uint, 0644);
EXPORT_SYMBOL_GPL(halt_poll_ns_grow_start);

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/* Default resets per-vcpu halt_poll_ns . */
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unsigned int halt_poll_ns_shrink;
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module_param(halt_poll_ns_shrink, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
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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_MUTEX(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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static struct kmem_cache *kvm_vcpu_cache;
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static __read_mostly struct preempt_ops kvm_preempt_ops;
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static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_running_vcpu);
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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;
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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);
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#define KVM_COMPAT(c)	.compat_ioctl	= (c)
#else
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/*
 * For architectures that don't implement a compat infrastructure,
 * adopt a double line of defense:
 * - Prevent a compat task from opening /dev/kvm
 * - If the open has been done by a 64bit task, and the KVM fd
 *   passed to a compat task, let the ioctls fail.
 */
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static long kvm_no_compat_ioctl(struct file *file, unsigned int ioctl,
				unsigned long arg) { return -EINVAL; }
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static int kvm_no_compat_open(struct inode *inode, struct file *file)
{
	return is_compat_task() ? -ENODEV : 0;
}
#define KVM_COMPAT(c)	.compat_ioctl	= kvm_no_compat_ioctl,	\
			.open		= kvm_no_compat_open
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#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 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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#define KVM_EVENT_CREATE_VM 0
#define KVM_EVENT_DESTROY_VM 1
static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm);
static unsigned long long kvm_createvm_count;
static unsigned long long kvm_active_vms;

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__weak int kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm,
		unsigned long start, unsigned long end, bool blockable)
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{
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	return 0;
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}

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bool kvm_is_zone_device_pfn(kvm_pfn_t pfn)
{
	/*
	 * The metadata used by is_zone_device_page() to determine whether or
	 * not a page is ZONE_DEVICE is guaranteed to be valid if and only if
	 * the device has been pinned, e.g. by get_user_pages().  WARN if the
	 * page_count() is zero to help detect bad usage of this helper.
	 */
	if (!pfn_valid(pfn) || WARN_ON_ONCE(!page_count(pfn_to_page(pfn))))
		return false;

	return is_zone_device_page(pfn_to_page(pfn));
}

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bool kvm_is_reserved_pfn(kvm_pfn_t pfn)
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{
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	/*
	 * ZONE_DEVICE pages currently set PG_reserved, but from a refcounting
	 * perspective they are "normal" pages, albeit with slightly different
	 * usage rules.
	 */
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	if (pfn_valid(pfn))
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		return PageReserved(pfn_to_page(pfn)) &&
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		       !is_zero_pfn(pfn) &&
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		       !kvm_is_zone_device_pfn(pfn);
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	return true;
}

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bool kvm_is_transparent_hugepage(kvm_pfn_t pfn)
{
	struct page *page = pfn_to_page(pfn);

	if (!PageTransCompoundMap(page))
		return false;

	return is_transparent_hugepage(compound_head(page));
}

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/*
 * Switches to specified vcpu, until a matching vcpu_put()
 */
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void vcpu_load(struct kvm_vcpu *vcpu)
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{
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	int cpu = get_cpu();
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	__this_cpu_write(kvm_running_vcpu, vcpu);
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	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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}
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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);
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	__this_cpu_write(kvm_running_vcpu, NULL);
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	preempt_enable();
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}
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EXPORT_SYMBOL_GPL(vcpu_put);
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/* TODO: merge with kvm_arch_vcpu_should_kick */
static bool kvm_request_needs_ipi(struct kvm_vcpu *vcpu, unsigned req)
{
	int mode = kvm_vcpu_exiting_guest_mode(vcpu);

	/*
	 * We need to wait for the VCPU to reenable interrupts and get out of
	 * READING_SHADOW_PAGE_TABLES mode.
	 */
	if (req & KVM_REQUEST_WAIT)
		return mode != OUTSIDE_GUEST_MODE;

	/*
	 * Need to kick a running VCPU, but otherwise there is nothing to do.
	 */
	return mode == IN_GUEST_MODE;
}

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static void ack_flush(void *_completed)
{
}

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static inline bool kvm_kick_many_cpus(const struct cpumask *cpus, bool wait)
{
	if (unlikely(!cpus))
		cpus = cpu_online_mask;

	if (cpumask_empty(cpus))
		return false;

	smp_call_function_many(cpus, ack_flush, NULL, wait);
	return true;
}

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bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
				 unsigned long *vcpu_bitmap, cpumask_var_t tmp)
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{
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	int i, cpu, me;
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	struct kvm_vcpu *vcpu;
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	bool called;
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	me = get_cpu();
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	kvm_for_each_vcpu(i, vcpu, kvm) {
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		if (vcpu_bitmap && !test_bit(i, vcpu_bitmap))
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			continue;

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		kvm_make_request(req, vcpu);
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		cpu = vcpu->cpu;
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		if (!(req & KVM_REQUEST_NO_WAKEUP) && kvm_vcpu_wake_up(vcpu))
			continue;
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		if (tmp != NULL && cpu != -1 && cpu != me &&
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		    kvm_request_needs_ipi(vcpu, req))
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			__cpumask_set_cpu(cpu, tmp);
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	}
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	called = kvm_kick_many_cpus(tmp, !!(req & KVM_REQUEST_WAIT));
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	put_cpu();
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	return called;
}

bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
{
	cpumask_var_t cpus;
	bool called;

	zalloc_cpumask_var(&cpus, GFP_ATOMIC);

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	called = kvm_make_vcpus_request_mask(kvm, req, NULL, cpus);
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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_arch_flush_remote_tlb(kvm)
	    || 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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static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
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{
	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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	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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	vcpu->ready = false;
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	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
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}

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void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
{
	kvm_arch_vcpu_destroy(vcpu);
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	/*
	 * No need for rcu_read_lock as VCPU_RUN is the only place that changes
	 * the vcpu->pid pointer, and at destruction time all file descriptors
	 * are already gone.
	 */
	put_pid(rcu_dereference_protected(vcpu->pid, 1));

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	free_page((unsigned long)vcpu->run);
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	kmem_cache_free(kvm_vcpu_cache, vcpu);
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}
EXPORT_SYMBOL_GPL(kvm_vcpu_destroy);

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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);
}

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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++;
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	if (kvm_set_spte_hva(kvm, address, pte))
		kvm_flush_remote_tlbs(kvm);

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

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static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
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					const struct mmu_notifier_range *range)
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{
	struct kvm *kvm = mmu_notifier_to_kvm(mn);
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	int need_tlb_flush = 0, idx;
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	int ret;
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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, range->start, range->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);
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	ret = kvm_arch_mmu_notifier_invalidate_range(kvm, range->start,
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					range->end,
					mmu_notifier_range_blockable(range));
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	srcu_read_unlock(&kvm->srcu, idx);
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	return ret;
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}

static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
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					const struct mmu_notifier_range *range)
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{
	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_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 = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
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	if (!slots)
		return NULL;

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	for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
569
		slots->id_to_index[i] = slots->memslots[i].id = i;
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607

	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);
608 609
}

610 611 612 613 614 615 616 617 618
static void kvm_destroy_vm_debugfs(struct kvm *kvm)
{
	int i;

	if (!kvm->debugfs_dentry)
		return;

	debugfs_remove_recursive(kvm->debugfs_dentry);

619 620 621 622 623
	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);
	}
624 625 626 627 628 629 630 631 632 633 634 635
}

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);
636
	kvm->debugfs_dentry = debugfs_create_dir(dir_name, kvm_debugfs_dir);
637 638 639

	kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
					 sizeof(*kvm->debugfs_stat_data),
640
					 GFP_KERNEL_ACCOUNT);
641 642 643 644
	if (!kvm->debugfs_stat_data)
		return -ENOMEM;

	for (p = debugfs_entries; p->name; p++) {
645
		stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
646 647 648 649
		if (!stat_data)
			return -ENOMEM;

		stat_data->kvm = kvm;
650
		stat_data->dbgfs_item = p;
651
		kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
652 653 654
		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
				    kvm->debugfs_dentry, stat_data,
				    &stat_fops_per_vm);
655 656 657 658
	}
	return 0;
}

659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675
/*
 * Called after the VM is otherwise initialized, but just before adding it to
 * the vm_list.
 */
int __weak kvm_arch_post_init_vm(struct kvm *kvm)
{
	return 0;
}

/*
 * Called just after removing the VM from the vm_list, but before doing any
 * other destruction.
 */
void __weak kvm_arch_pre_destroy_vm(struct kvm *kvm)
{
}

676
static struct kvm *kvm_create_vm(unsigned long type)
A
Avi Kivity 已提交
677
{
678
	struct kvm *kvm = kvm_arch_alloc_vm();
679 680
	int r = -ENOMEM;
	int i;
A
Avi Kivity 已提交
681

682 683 684
	if (!kvm)
		return ERR_PTR(-ENOMEM);

685
	spin_lock_init(&kvm->mmu_lock);
V
Vegard Nossum 已提交
686
	mmgrab(current->mm);
687 688 689 690 691 692 693
	kvm->mm = current->mm;
	kvm_eventfd_init(kvm);
	mutex_init(&kvm->lock);
	mutex_init(&kvm->irq_lock);
	mutex_init(&kvm->slots_lock);
	INIT_LIST_HEAD(&kvm->devices);

694 695
	BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);

696 697 698 699 700
	if (init_srcu_struct(&kvm->srcu))
		goto out_err_no_srcu;
	if (init_srcu_struct(&kvm->irq_srcu))
		goto out_err_no_irq_srcu;

701
	refcount_set(&kvm->users_count, 1);
702
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
703
		struct kvm_memslots *slots = kvm_alloc_memslots();
704

705
		if (!slots)
706
			goto out_err_no_arch_destroy_vm;
707
		/* Generations must be different for each address space. */
708
		slots->generation = i;
709
		rcu_assign_pointer(kvm->memslots[i], slots);
710
	}
711

M
Marcelo Tosatti 已提交
712
	for (i = 0; i < KVM_NR_BUSES; i++) {
713
		rcu_assign_pointer(kvm->buses[i],
714
			kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL_ACCOUNT));
715
		if (!kvm->buses[i])
716
			goto out_err_no_arch_destroy_vm;
M
Marcelo Tosatti 已提交
717
	}
718

719
	r = kvm_arch_init_vm(kvm, type);
720
	if (r)
721
		goto out_err_no_arch_destroy_vm;
722 723 724

	r = hardware_enable_all();
	if (r)
725
		goto out_err_no_disable;
726

727
#ifdef CONFIG_HAVE_KVM_IRQFD
728
	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
729
#endif
A
Avi Kivity 已提交
730

731
	r = kvm_init_mmu_notifier(kvm);
732 733 734 735
	if (r)
		goto out_err_no_mmu_notifier;

	r = kvm_arch_post_init_vm(kvm);
736 737 738
	if (r)
		goto out_err;

J
Junaid Shahid 已提交
739
	mutex_lock(&kvm_lock);
740
	list_add(&kvm->vm_list, &vm_list);
J
Junaid Shahid 已提交
741
	mutex_unlock(&kvm_lock);
742

743 744
	preempt_notifier_inc();

745
	return kvm;
746 747

out_err:
748 749 750 751 752
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
	if (kvm->mmu_notifier.ops)
		mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
#endif
out_err_no_mmu_notifier:
753
	hardware_disable_all();
754
out_err_no_disable:
755 756
	kvm_arch_destroy_vm(kvm);
out_err_no_arch_destroy_vm:
757
	WARN_ON_ONCE(!refcount_dec_and_test(&kvm->users_count));
M
Marcelo Tosatti 已提交
758
	for (i = 0; i < KVM_NR_BUSES; i++)
759
		kfree(kvm_get_bus(kvm, i));
760
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
761
		kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
762 763 764 765
	cleanup_srcu_struct(&kvm->irq_srcu);
out_err_no_irq_srcu:
	cleanup_srcu_struct(&kvm->srcu);
out_err_no_srcu:
766
	kvm_arch_free_vm(kvm);
767
	mmdrop(current->mm);
768
	return ERR_PTR(r);
769 770
}

771 772
static void kvm_destroy_devices(struct kvm *kvm)
{
G
Geliang Tang 已提交
773
	struct kvm_device *dev, *tmp;
774

775 776 777 778 779
	/*
	 * 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
780 781
	list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
		list_del(&dev->vm_node);
782 783 784 785
		dev->ops->destroy(dev);
	}
}

786 787
static void kvm_destroy_vm(struct kvm *kvm)
{
M
Marcelo Tosatti 已提交
788
	int i;
789 790
	struct mm_struct *mm = kvm->mm;

791
	kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
792
	kvm_destroy_vm_debugfs(kvm);
793
	kvm_arch_sync_events(kvm);
J
Junaid Shahid 已提交
794
	mutex_lock(&kvm_lock);
795
	list_del(&kvm->vm_list);
J
Junaid Shahid 已提交
796
	mutex_unlock(&kvm_lock);
797 798
	kvm_arch_pre_destroy_vm(kvm);

799
	kvm_free_irq_routing(kvm);
800
	for (i = 0; i < KVM_NR_BUSES; i++) {
801
		struct kvm_io_bus *bus = kvm_get_bus(kvm, i);
802 803 804

		if (bus)
			kvm_io_bus_destroy(bus);
805 806
		kvm->buses[i] = NULL;
	}
807
	kvm_coalesced_mmio_free(kvm);
808 809
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
	mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
810
#else
811
	kvm_arch_flush_shadow_all(kvm);
812
#endif
813
	kvm_arch_destroy_vm(kvm);
814
	kvm_destroy_devices(kvm);
815
	for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
816
		kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
817
	cleanup_srcu_struct(&kvm->irq_srcu);
818 819
	cleanup_srcu_struct(&kvm->srcu);
	kvm_arch_free_vm(kvm);
820
	preempt_notifier_dec();
821
	hardware_disable_all();
822
	mmdrop(mm);
823 824
}

I
Izik Eidus 已提交
825 826
void kvm_get_kvm(struct kvm *kvm)
{
827
	refcount_inc(&kvm->users_count);
I
Izik Eidus 已提交
828 829 830 831 832
}
EXPORT_SYMBOL_GPL(kvm_get_kvm);

void kvm_put_kvm(struct kvm *kvm)
{
833
	if (refcount_dec_and_test(&kvm->users_count))
I
Izik Eidus 已提交
834 835 836 837
		kvm_destroy_vm(kvm);
}
EXPORT_SYMBOL_GPL(kvm_put_kvm);

838 839 840 841 842 843 844 845 846 847 848 849
/*
 * Used to put a reference that was taken on behalf of an object associated
 * with a user-visible file descriptor, e.g. a vcpu or device, if installation
 * of the new file descriptor fails and the reference cannot be transferred to
 * its final owner.  In such cases, the caller is still actively using @kvm and
 * will fail miserably if the refcount unexpectedly hits zero.
 */
void kvm_put_kvm_no_destroy(struct kvm *kvm)
{
	WARN_ON(refcount_dec_and_test(&kvm->users_count));
}
EXPORT_SYMBOL_GPL(kvm_put_kvm_no_destroy);
I
Izik Eidus 已提交
850

851 852 853 854
static int kvm_vm_release(struct inode *inode, struct file *filp)
{
	struct kvm *kvm = filp->private_data;

G
Gregory Haskins 已提交
855 856
	kvm_irqfd_release(kvm);

I
Izik Eidus 已提交
857
	kvm_put_kvm(kvm);
A
Avi Kivity 已提交
858 859 860
	return 0;
}

861 862
/*
 * Allocation size is twice as large as the actual dirty bitmap size.
863
 * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
864
 */
865 866
static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
{
867
	unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
868

869
	memslot->dirty_bitmap = kvzalloc(dirty_bytes, GFP_KERNEL_ACCOUNT);
870 871 872 873 874 875
	if (!memslot->dirty_bitmap)
		return -ENOMEM;

	return 0;
}

876
/*
877 878 879 880
 * 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.
881
 */
882
static void update_memslots(struct kvm_memslots *slots,
883 884
			    struct kvm_memory_slot *new,
			    enum kvm_mr_change change)
885
{
886 887
	int id = new->id;
	int i = slots->id_to_index[id];
888
	struct kvm_memory_slot *mslots = slots->memslots;
889

890
	WARN_ON(mslots[i].id != id);
891 892 893 894 895 896 897 898 899 900 901
	switch (change) {
	case KVM_MR_CREATE:
		slots->used_slots++;
		WARN_ON(mslots[i].npages || !new->npages);
		break;
	case KVM_MR_DELETE:
		slots->used_slots--;
		WARN_ON(new->npages || !mslots[i].npages);
		break;
	default:
		break;
902
	}
903

904
	while (i < KVM_MEM_SLOTS_NUM - 1 &&
905 906 907
	       new->base_gfn <= mslots[i + 1].base_gfn) {
		if (!mslots[i + 1].npages)
			break;
908 909 910 911
		mslots[i] = mslots[i + 1];
		slots->id_to_index[mslots[i].id] = i;
		i++;
	}
912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928

	/*
	 * 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--;
		}
929 930
	} else
		WARN_ON_ONCE(i != slots->used_slots);
931

932 933
	mslots[i] = *new;
	slots->id_to_index[mslots[i].id] = i;
934 935
}

936
static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
937
{
X
Xiao Guangrong 已提交
938 939
	u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;

940
#ifdef __KVM_HAVE_READONLY_MEM
X
Xiao Guangrong 已提交
941 942 943 944
	valid_flags |= KVM_MEM_READONLY;
#endif

	if (mem->flags & ~valid_flags)
945 946 947 948 949
		return -EINVAL;

	return 0;
}

950
static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
951
		int as_id, struct kvm_memslots *slots)
952
{
953
	struct kvm_memslots *old_memslots = __kvm_memslots(kvm, as_id);
954
	u64 gen = old_memslots->generation;
955

956 957
	WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
	slots->generation = gen | KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
958

959
	rcu_assign_pointer(kvm->memslots[as_id], slots);
960
	synchronize_srcu_expedited(&kvm->srcu);
961

962
	/*
963
	 * Increment the new memslot generation a second time, dropping the
M
Miaohe Lin 已提交
964
	 * update in-progress flag and incrementing the generation based on
965 966 967 968 969 970
	 * the number of address spaces.  This provides a unique and easily
	 * identifiable generation number while the memslots are in flux.
	 */
	gen = slots->generation & ~KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;

	/*
971 972 973
	 * Generations must be unique even across address spaces.  We do not need
	 * a global counter for that, instead the generation space is evenly split
	 * across address spaces.  For example, with two address spaces, address
974 975
	 * space 0 will use generations 0, 2, 4, ... while address space 1 will
	 * use generations 1, 3, 5, ...
976
	 */
977
	gen += KVM_ADDRESS_SPACE_NUM;
978

979
	kvm_arch_memslots_updated(kvm, gen);
980

981
	slots->generation = gen;
982 983

	return old_memslots;
984 985
}

A
Avi Kivity 已提交
986 987 988 989 990
/*
 * Allocate some memory and give it an address in the guest physical address
 * space.
 *
 * Discontiguous memory is allowed, mostly for framebuffers.
991
 *
992
 * Must be called holding kvm->slots_lock for write.
A
Avi Kivity 已提交
993
 */
994
int __kvm_set_memory_region(struct kvm *kvm,
995
			    const struct kvm_userspace_memory_region *mem)
A
Avi Kivity 已提交
996
{
997
	int r;
A
Avi Kivity 已提交
998
	gfn_t base_gfn;
999
	unsigned long npages;
1000
	struct kvm_memory_slot *slot;
A
Avi Kivity 已提交
1001
	struct kvm_memory_slot old, new;
1002
	struct kvm_memslots *slots;
1003
	int as_id, id;
1004
	enum kvm_mr_change change;
A
Avi Kivity 已提交
1005

1006 1007 1008 1009
	r = check_memory_region_flags(mem);
	if (r)
		goto out;

A
Avi Kivity 已提交
1010
	r = -EINVAL;
1011 1012 1013
	as_id = mem->slot >> 16;
	id = (u16)mem->slot;

A
Avi Kivity 已提交
1014 1015 1016 1017 1018
	/* General sanity checks */
	if (mem->memory_size & (PAGE_SIZE - 1))
		goto out;
	if (mem->guest_phys_addr & (PAGE_SIZE - 1))
		goto out;
1019
	/* We can read the guest memory with __xxx_user() later on. */
1020
	if ((id < KVM_USER_MEM_SLOTS) &&
1021
	    ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
1022
	     !access_ok((void __user *)(unsigned long)mem->userspace_addr,
1023
			mem->memory_size)))
1024
		goto out;
1025
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
A
Avi Kivity 已提交
1026 1027 1028 1029
		goto out;
	if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
		goto out;

1030
	slot = id_to_memslot(__kvm_memslots(kvm, as_id), id);
A
Avi Kivity 已提交
1031 1032 1033
	base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
	npages = mem->memory_size >> PAGE_SHIFT;

1034 1035 1036
	if (npages > KVM_MEM_MAX_NR_PAGES)
		goto out;

1037
	new = old = *slot;
A
Avi Kivity 已提交
1038

1039
	new.id = id;
A
Avi Kivity 已提交
1040 1041 1042 1043
	new.base_gfn = base_gfn;
	new.npages = npages;
	new.flags = mem->flags;

1044 1045 1046 1047 1048
	if (npages) {
		if (!old.npages)
			change = KVM_MR_CREATE;
		else { /* Modify an existing slot. */
			if ((mem->userspace_addr != old.userspace_addr) ||
1049 1050
			    (npages != old.npages) ||
			    ((new.flags ^ old.flags) & KVM_MEM_READONLY))
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061
				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;
			}
		}
1062 1063 1064 1065
	} else {
		if (!old.npages)
			goto out;

1066
		change = KVM_MR_DELETE;
1067 1068 1069
		new.base_gfn = 0;
		new.flags = 0;
	}
A
Avi Kivity 已提交
1070

1071
	if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
1072 1073
		/* Check for overlaps */
		r = -EEXIST;
1074
		kvm_for_each_memslot(slot, __kvm_memslots(kvm, as_id)) {
1075
			if (slot->id == id)
1076 1077 1078 1079 1080
				continue;
			if (!((base_gfn + npages <= slot->base_gfn) ||
			      (base_gfn >= slot->base_gfn + slot->npages)))
				goto out;
		}
A
Avi Kivity 已提交
1081 1082 1083 1084
	}

	/* Free page dirty bitmap if unneeded */
	if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
A
Al Viro 已提交
1085
		new.dirty_bitmap = NULL;
A
Avi Kivity 已提交
1086 1087

	r = -ENOMEM;
1088
	if (change == KVM_MR_CREATE) {
1089
		new.userspace_addr = mem->userspace_addr;
1090

1091
		if (kvm_arch_create_memslot(kvm, &new, npages))
1092
			goto out;
A
Avi Kivity 已提交
1093
	}
1094

A
Avi Kivity 已提交
1095 1096
	/* Allocate page dirty bitmap if needed */
	if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
1097
		if (kvm_create_dirty_bitmap(&new) < 0)
1098
			goto out_free;
A
Avi Kivity 已提交
1099 1100
	}

1101
	slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
1102 1103
	if (!slots)
		goto out_free;
1104
	memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));
1105

1106
	if ((change == KVM_MR_DELETE) || (change == KVM_MR_MOVE)) {
1107
		slot = id_to_memslot(slots, id);
1108 1109
		slot->flags |= KVM_MEMSLOT_INVALID;

1110 1111 1112 1113 1114 1115 1116
		/*
		 * We can re-use the old memslots, the only difference from the
		 * newly installed memslots is the invalid flag, which will get
		 * dropped by update_memslots anyway.  We'll also revert to the
		 * old memslots if preparing the new memory region fails.
		 */
		slots = install_new_memslots(kvm, as_id, slots);
1117

1118 1119
		/* From this point no new shadow pages pointing to a deleted,
		 * or moved, memslot will be created.
1120 1121
		 *
		 * validation of sp->gfn happens in:
1122
		 *	- gfn_to_hva (kvm_read_guest, gfn_to_pfn)
1123
		 *	- kvm_is_visible_gfn (mmu_check_root)
1124
		 */
1125
		kvm_arch_flush_shadow_memslot(kvm, slot);
1126
	}
1127

1128
	r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
1129
	if (r)
1130
		goto out_slots;
1131

1132
	/* actual memory is freed via old in kvm_free_memslot below */
1133
	if (change == KVM_MR_DELETE) {
1134
		new.dirty_bitmap = NULL;
1135
		memset(&new.arch, 0, sizeof(new.arch));
1136 1137
	}

1138
	update_memslots(slots, &new, change);
1139
	slots = install_new_memslots(kvm, as_id, slots);
1140

1141
	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);
1142

1143
	kvm_free_memslot(kvm, &old, &new);
1144
	kvfree(slots);
A
Avi Kivity 已提交
1145 1146
	return 0;

1147
out_slots:
1148 1149
	if (change == KVM_MR_DELETE || change == KVM_MR_MOVE)
		slots = install_new_memslots(kvm, as_id, slots);
1150
	kvfree(slots);
1151
out_free:
1152
	kvm_free_memslot(kvm, &new, &old);
A
Avi Kivity 已提交
1153 1154
out:
	return r;
1155
}
1156 1157 1158
EXPORT_SYMBOL_GPL(__kvm_set_memory_region);

int kvm_set_memory_region(struct kvm *kvm,
1159
			  const struct kvm_userspace_memory_region *mem)
1160 1161 1162
{
	int r;

1163
	mutex_lock(&kvm->slots_lock);
1164
	r = __kvm_set_memory_region(kvm, mem);
1165
	mutex_unlock(&kvm->slots_lock);
1166 1167
	return r;
}
1168 1169
EXPORT_SYMBOL_GPL(kvm_set_memory_region);

1170 1171
static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
					  struct kvm_userspace_memory_region *mem)
1172
{
1173
	if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
1174
		return -EINVAL;
1175

1176
	return kvm_set_memory_region(kvm, mem);
A
Avi Kivity 已提交
1177 1178
}

1179 1180
int kvm_get_dirty_log(struct kvm *kvm,
			struct kvm_dirty_log *log, int *is_dirty)
A
Avi Kivity 已提交
1181
{
1182
	struct kvm_memslots *slots;
A
Avi Kivity 已提交
1183
	struct kvm_memory_slot *memslot;
1184
	int i, as_id, id;
1185
	unsigned long n;
A
Avi Kivity 已提交
1186 1187
	unsigned long any = 0;

1188 1189 1190
	as_id = log->slot >> 16;
	id = (u16)log->slot;
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1191
		return -EINVAL;
A
Avi Kivity 已提交
1192

1193 1194
	slots = __kvm_memslots(kvm, as_id);
	memslot = id_to_memslot(slots, id);
A
Avi Kivity 已提交
1195
	if (!memslot->dirty_bitmap)
1196
		return -ENOENT;
A
Avi Kivity 已提交
1197

1198
	n = kvm_dirty_bitmap_bytes(memslot);
A
Avi Kivity 已提交
1199

1200
	for (i = 0; !any && i < n/sizeof(long); ++i)
A
Avi Kivity 已提交
1201 1202 1203
		any = memslot->dirty_bitmap[i];

	if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
1204
		return -EFAULT;
A
Avi Kivity 已提交
1205

1206 1207
	if (any)
		*is_dirty = 1;
1208
	return 0;
A
Avi Kivity 已提交
1209
}
1210
EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
A
Avi Kivity 已提交
1211

1212 1213
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
/**
J
Jiang Biao 已提交
1214
 * kvm_get_dirty_log_protect - get a snapshot of dirty pages
1215
 *	and reenable dirty page tracking for the corresponding pages.
1216 1217
 * @kvm:	pointer to kvm instance
 * @log:	slot id and address to which we copy the log
J
Jiang Biao 已提交
1218
 * @flush:	true if TLB flush is needed by caller
1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235
 *
 * 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,
1236
			struct kvm_dirty_log *log, bool *flush)
1237
{
1238
	struct kvm_memslots *slots;
1239
	struct kvm_memory_slot *memslot;
1240
	int i, as_id, id;
1241 1242 1243 1244
	unsigned long n;
	unsigned long *dirty_bitmap;
	unsigned long *dirty_bitmap_buffer;

1245 1246 1247
	as_id = log->slot >> 16;
	id = (u16)log->slot;
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
1248
		return -EINVAL;
1249

1250 1251
	slots = __kvm_memslots(kvm, as_id);
	memslot = id_to_memslot(slots, id);
1252 1253 1254

	dirty_bitmap = memslot->dirty_bitmap;
	if (!dirty_bitmap)
1255
		return -ENOENT;
1256 1257

	n = kvm_dirty_bitmap_bytes(memslot);
1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271
	*flush = false;
	if (kvm->manual_dirty_log_protect) {
		/*
		 * Unlike kvm_get_dirty_log, we always return false in *flush,
		 * because no flush is needed until KVM_CLEAR_DIRTY_LOG.  There
		 * is some code duplication between this function and
		 * kvm_get_dirty_log, but hopefully all architecture
		 * transition to kvm_get_dirty_log_protect and kvm_get_dirty_log
		 * can be eliminated.
		 */
		dirty_bitmap_buffer = dirty_bitmap;
	} else {
		dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
		memset(dirty_bitmap_buffer, 0, n);
1272

1273 1274 1275 1276
		spin_lock(&kvm->mmu_lock);
		for (i = 0; i < n / sizeof(long); i++) {
			unsigned long mask;
			gfn_t offset;
1277

1278 1279 1280 1281 1282 1283 1284
			if (!dirty_bitmap[i])
				continue;

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

1285 1286 1287
			offset = i * BITS_PER_LONG;
			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
								offset, mask);
1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302
		}
		spin_unlock(&kvm->mmu_lock);
	}

	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
		return -EFAULT;
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);

/**
 * kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
 *	and reenable dirty page tracking for the corresponding pages.
 * @kvm:	pointer to kvm instance
 * @log:	slot id and address from which to fetch the bitmap of dirty pages
J
Jiang Biao 已提交
1303
 * @flush:	true if TLB flush is needed by caller
1304 1305 1306 1307 1308 1309
 */
int kvm_clear_dirty_log_protect(struct kvm *kvm,
				struct kvm_clear_dirty_log *log, bool *flush)
{
	struct kvm_memslots *slots;
	struct kvm_memory_slot *memslot;
1310
	int as_id, id;
1311
	gfn_t offset;
1312
	unsigned long i, n;
1313 1314 1315 1316 1317 1318 1319 1320
	unsigned long *dirty_bitmap;
	unsigned long *dirty_bitmap_buffer;

	as_id = log->slot >> 16;
	id = (u16)log->slot;
	if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
		return -EINVAL;

1321
	if (log->first_page & 63)
1322 1323 1324 1325 1326 1327 1328 1329 1330
		return -EINVAL;

	slots = __kvm_memslots(kvm, as_id);
	memslot = id_to_memslot(slots, id);

	dirty_bitmap = memslot->dirty_bitmap;
	if (!dirty_bitmap)
		return -ENOENT;

1331
	n = ALIGN(log->num_pages, BITS_PER_LONG) / 8;
1332 1333

	if (log->first_page > memslot->npages ||
1334 1335 1336
	    log->num_pages > memslot->npages - log->first_page ||
	    (log->num_pages < memslot->npages - log->first_page && (log->num_pages & 63)))
	    return -EINVAL;
1337

1338
	*flush = false;
1339 1340 1341
	dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
	if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
		return -EFAULT;
1342

1343
	spin_lock(&kvm->mmu_lock);
1344 1345
	for (offset = log->first_page, i = offset / BITS_PER_LONG,
		 n = DIV_ROUND_UP(log->num_pages, BITS_PER_LONG); n--;
1346 1347 1348 1349
	     i++, offset += BITS_PER_LONG) {
		unsigned long mask = *dirty_bitmap_buffer++;
		atomic_long_t *p = (atomic_long_t *) &dirty_bitmap[i];
		if (!mask)
1350 1351
			continue;

1352
		mask &= atomic_long_fetch_andnot(mask, p);
1353

1354 1355 1356 1357 1358 1359
		/*
		 * mask contains the bits that really have been cleared.  This
		 * never includes any bits beyond the length of the memslot (if
		 * the length is not aligned to 64 pages), therefore it is not
		 * a problem if userspace sets them in log->dirty_bitmap.
		*/
1360
		if (mask) {
1361
			*flush = true;
1362 1363 1364
			kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
								offset, mask);
		}
1365 1366
	}
	spin_unlock(&kvm->mmu_lock);
1367

1368
	return 0;
1369
}
1370
EXPORT_SYMBOL_GPL(kvm_clear_dirty_log_protect);
1371 1372
#endif

1373 1374 1375 1376 1377
bool kvm_largepages_enabled(void)
{
	return largepages_enabled;
}

1378 1379 1380 1381 1382 1383
void kvm_disable_largepages(void)
{
	largepages_enabled = false;
}
EXPORT_SYMBOL_GPL(kvm_disable_largepages);

1384 1385 1386 1387
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
1388
EXPORT_SYMBOL_GPL(gfn_to_memslot);
A
Avi Kivity 已提交
1389

1390 1391 1392 1393 1394
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);
}

1395
bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
1396
{
1397
	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
1398

1399
	if (!memslot || memslot->id >= KVM_USER_MEM_SLOTS ||
1400
	      memslot->flags & KVM_MEMSLOT_INVALID)
1401
		return false;
1402

1403
	return true;
1404 1405 1406
}
EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);

1407
unsigned long kvm_host_page_size(struct kvm_vcpu *vcpu, gfn_t gfn)
J
Joerg Roedel 已提交
1408 1409 1410 1411 1412 1413
{
	struct vm_area_struct *vma;
	unsigned long addr, size;

	size = PAGE_SIZE;

1414
	addr = kvm_vcpu_gfn_to_hva_prot(vcpu, gfn, NULL);
J
Joerg Roedel 已提交
1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430
	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
1431 1432 1433 1434 1435 1436 1437
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
1438
{
1439
	if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
X
Xiao Guangrong 已提交
1440
		return KVM_HVA_ERR_BAD;
1441

X
Xiao Guangrong 已提交
1442 1443
	if (memslot_is_readonly(slot) && write)
		return KVM_HVA_ERR_RO_BAD;
1444 1445 1446 1447

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

X
Xiao Guangrong 已提交
1448
	return __gfn_to_hva_memslot(slot, gfn);
I
Izik Eidus 已提交
1449
}
1450

X
Xiao Guangrong 已提交
1451 1452 1453 1454
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
1455
}
1456

X
Xiao Guangrong 已提交
1457
unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
1458
					gfn_t gfn)
X
Xiao Guangrong 已提交
1459 1460 1461 1462 1463
{
	return gfn_to_hva_many(slot, gfn, NULL);
}
EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);

1464 1465
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
{
1466
	return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
1467
}
1468
EXPORT_SYMBOL_GPL(gfn_to_hva);
I
Izik Eidus 已提交
1469

1470 1471 1472 1473 1474 1475
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);

1476
/*
1477 1478 1479 1480 1481 1482
 * Return the hva of a @gfn and the R/W attribute if possible.
 *
 * @slot: the kvm_memory_slot which contains @gfn
 * @gfn: the gfn to be translated
 * @writable: used to return the read/write attribute of the @slot if the hva
 * is valid and @writable is not NULL
1483
 */
1484 1485
unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
				      gfn_t gfn, bool *writable)
1486
{
1487 1488 1489
	unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);

	if (!kvm_is_error_hva(hva) && writable)
1490 1491
		*writable = !memslot_is_readonly(slot);

1492
	return hva;
1493 1494
}

1495 1496 1497 1498 1499 1500 1501
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);
}

1502 1503 1504 1505 1506 1507 1508
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);
}

1509 1510
static inline int check_user_page_hwpoison(unsigned long addr)
{
L
Lorenzo Stoakes 已提交
1511
	int rc, flags = FOLL_HWPOISON | FOLL_WRITE;
1512

L
Lorenzo Stoakes 已提交
1513
	rc = get_user_pages(addr, 1, flags, NULL, NULL);
1514 1515 1516
	return rc == -EHWPOISON;
}

X
Xiao Guangrong 已提交
1517
/*
1518 1519
 * The fast path to get the writable pfn which will be stored in @pfn,
 * true indicates success, otherwise false is returned.  It's also the
M
Miaohe Lin 已提交
1520
 * only part that runs if we can in atomic context.
X
Xiao Guangrong 已提交
1521
 */
1522 1523
static bool hva_to_pfn_fast(unsigned long addr, bool write_fault,
			    bool *writable, kvm_pfn_t *pfn)
A
Avi Kivity 已提交
1524
{
1525
	struct page *page[1];
X
Xiao Guangrong 已提交
1526
	int npages;
A
Avi Kivity 已提交
1527

1528 1529 1530 1531 1532 1533 1534
	/*
	 * 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;
1535

X
Xiao Guangrong 已提交
1536 1537 1538
	npages = __get_user_pages_fast(addr, 1, 1, page);
	if (npages == 1) {
		*pfn = page_to_pfn(page[0]);
1539

X
Xiao Guangrong 已提交
1540 1541 1542 1543
		if (writable)
			*writable = true;
		return true;
	}
1544

X
Xiao Guangrong 已提交
1545 1546
	return false;
}
1547

X
Xiao Guangrong 已提交
1548 1549 1550 1551 1552
/*
 * 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
1553
			   bool *writable, kvm_pfn_t *pfn)
X
Xiao Guangrong 已提交
1554
{
1555 1556
	unsigned int flags = FOLL_HWPOISON;
	struct page *page;
X
Xiao Guangrong 已提交
1557
	int npages = 0;
1558

X
Xiao Guangrong 已提交
1559 1560 1561 1562 1563
	might_sleep();

	if (writable)
		*writable = write_fault;

1564 1565 1566 1567
	if (write_fault)
		flags |= FOLL_WRITE;
	if (async)
		flags |= FOLL_NOWAIT;
1568

1569
	npages = get_user_pages_unlocked(addr, 1, &page, flags);
X
Xiao Guangrong 已提交
1570 1571 1572 1573
	if (npages != 1)
		return npages;

	/* map read fault as writable if possible */
1574
	if (unlikely(!write_fault) && writable) {
1575
		struct page *wpage;
X
Xiao Guangrong 已提交
1576

1577
		if (__get_user_pages_fast(addr, 1, 1, &wpage) == 1) {
X
Xiao Guangrong 已提交
1578
			*writable = true;
1579 1580
			put_page(page);
			page = wpage;
1581
		}
1582
	}
1583
	*pfn = page_to_pfn(page);
X
Xiao Guangrong 已提交
1584 1585
	return npages;
}
I
Izik Eidus 已提交
1586

X
Xiao Guangrong 已提交
1587 1588 1589 1590
static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
{
	if (unlikely(!(vma->vm_flags & VM_READ)))
		return false;
1591

X
Xiao Guangrong 已提交
1592 1593
	if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
		return false;
1594

X
Xiao Guangrong 已提交
1595 1596
	return true;
}
1597

1598 1599
static int hva_to_pfn_remapped(struct vm_area_struct *vma,
			       unsigned long addr, bool *async,
1600 1601
			       bool write_fault, bool *writable,
			       kvm_pfn_t *p_pfn)
1602
{
1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626
	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;

	}

1627 1628
	if (writable)
		*writable = true;
1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643

	/*
	 * 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;
1644 1645 1646
	return 0;
}

1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660
/*
 * 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
1661
static kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
X
Xiao Guangrong 已提交
1662 1663 1664
			bool write_fault, bool *writable)
{
	struct vm_area_struct *vma;
D
Dan Williams 已提交
1665
	kvm_pfn_t pfn = 0;
1666
	int npages, r;
1667

X
Xiao Guangrong 已提交
1668 1669
	/* we can do it either atomically or asynchronously, not both */
	BUG_ON(atomic && async);
1670

1671
	if (hva_to_pfn_fast(addr, write_fault, writable, &pfn))
X
Xiao Guangrong 已提交
1672 1673 1674 1675 1676 1677 1678 1679
		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;
1680

X
Xiao Guangrong 已提交
1681 1682 1683 1684 1685 1686 1687
	down_read(&current->mm->mmap_sem);
	if (npages == -EHWPOISON ||
	      (!async && check_user_page_hwpoison(addr))) {
		pfn = KVM_PFN_ERR_HWPOISON;
		goto exit;
	}

1688
retry:
X
Xiao Guangrong 已提交
1689 1690 1691 1692
	vma = find_vma_intersection(current->mm, addr, addr + 1);

	if (vma == NULL)
		pfn = KVM_PFN_ERR_FAULT;
1693
	else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) {
1694
		r = hva_to_pfn_remapped(vma, addr, async, write_fault, writable, &pfn);
1695 1696
		if (r == -EAGAIN)
			goto retry;
1697 1698
		if (r < 0)
			pfn = KVM_PFN_ERR_FAULT;
X
Xiao Guangrong 已提交
1699
	} else {
X
Xiao Guangrong 已提交
1700
		if (async && vma_is_valid(vma, write_fault))
X
Xiao Guangrong 已提交
1701 1702 1703 1704 1705
			*async = true;
		pfn = KVM_PFN_ERR_FAULT;
	}
exit:
	up_read(&current->mm->mmap_sem);
1706
	return pfn;
1707 1708
}

D
Dan Williams 已提交
1709 1710 1711
kvm_pfn_t __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn,
			       bool atomic, bool *async, bool write_fault,
			       bool *writable)
1712
{
X
Xiao Guangrong 已提交
1713 1714
	unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault);

1715 1716 1717
	if (addr == KVM_HVA_ERR_RO_BAD) {
		if (writable)
			*writable = false;
X
Xiao Guangrong 已提交
1718
		return KVM_PFN_ERR_RO_FAULT;
1719
	}
X
Xiao Guangrong 已提交
1720

1721 1722 1723
	if (kvm_is_error_hva(addr)) {
		if (writable)
			*writable = false;
1724
		return KVM_PFN_NOSLOT;
1725
	}
X
Xiao Guangrong 已提交
1726 1727 1728 1729 1730 1731 1732 1733 1734

	/* 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);
1735
}
1736
EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot);
1737

D
Dan Williams 已提交
1738
kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault,
1739 1740
		      bool *writable)
{
P
Paolo Bonzini 已提交
1741 1742
	return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL,
				    write_fault, writable);
1743 1744 1745
}
EXPORT_SYMBOL_GPL(gfn_to_pfn_prot);

D
Dan Williams 已提交
1746
kvm_pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn)
1747
{
X
Xiao Guangrong 已提交
1748
	return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL);
1749
}
P
Paolo Bonzini 已提交
1750
EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot);
1751

D
Dan Williams 已提交
1752
kvm_pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn)
1753
{
X
Xiao Guangrong 已提交
1754
	return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL);
1755
}
1756
EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
1757

D
Dan Williams 已提交
1758
kvm_pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn)
P
Paolo Bonzini 已提交
1759 1760 1761 1762 1763
{
	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
1764
kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
1765 1766 1767 1768 1769
{
	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
1770
kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
P
Paolo Bonzini 已提交
1771 1772 1773 1774 1775
{
	return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
}
EXPORT_SYMBOL_GPL(gfn_to_pfn);

D
Dan Williams 已提交
1776
kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
1777 1778 1779 1780 1781
{
	return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);

1782 1783
int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
			    struct page **pages, int nr_pages)
1784 1785
{
	unsigned long addr;
1786
	gfn_t entry = 0;
1787

1788
	addr = gfn_to_hva_many(slot, gfn, &entry);
1789 1790 1791 1792 1793 1794 1795 1796 1797 1798
	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
1799
static struct page *kvm_pfn_to_page(kvm_pfn_t pfn)
X
Xiao Guangrong 已提交
1800
{
1801
	if (is_error_noslot_pfn(pfn))
1802
		return KVM_ERR_PTR_BAD_PAGE;
X
Xiao Guangrong 已提交
1803

1804
	if (kvm_is_reserved_pfn(pfn)) {
1805
		WARN_ON(1);
1806
		return KVM_ERR_PTR_BAD_PAGE;
1807
	}
X
Xiao Guangrong 已提交
1808 1809 1810 1811

	return pfn_to_page(pfn);
}

1812 1813
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
{
D
Dan Williams 已提交
1814
	kvm_pfn_t pfn;
1815 1816 1817

	pfn = gfn_to_pfn(kvm, gfn);

X
Xiao Guangrong 已提交
1818
	return kvm_pfn_to_page(pfn);
A
Avi Kivity 已提交
1819 1820 1821
}
EXPORT_SYMBOL_GPL(gfn_to_page);

1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846
void kvm_release_pfn(kvm_pfn_t pfn, bool dirty, struct gfn_to_pfn_cache *cache)
{
	if (pfn == 0)
		return;

	if (cache)
		cache->pfn = cache->gfn = 0;

	if (dirty)
		kvm_release_pfn_dirty(pfn);
	else
		kvm_release_pfn_clean(pfn);
}

static void kvm_cache_gfn_to_pfn(struct kvm_memory_slot *slot, gfn_t gfn,
				 struct gfn_to_pfn_cache *cache, u64 gen)
{
	kvm_release_pfn(cache->pfn, cache->dirty, cache);

	cache->pfn = gfn_to_pfn_memslot(slot, gfn);
	cache->gfn = gfn;
	cache->dirty = false;
	cache->generation = gen;
}

1847
static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn,
1848 1849 1850
			 struct kvm_host_map *map,
			 struct gfn_to_pfn_cache *cache,
			 bool atomic)
1851 1852 1853 1854
{
	kvm_pfn_t pfn;
	void *hva = NULL;
	struct page *page = KVM_UNMAPPED_PAGE;
1855
	struct kvm_memory_slot *slot = __gfn_to_memslot(slots, gfn);
1856
	u64 gen = slots->generation;
1857 1858 1859 1860

	if (!map)
		return -EINVAL;

1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873
	if (cache) {
		if (!cache->pfn || cache->gfn != gfn ||
			cache->generation != gen) {
			if (atomic)
				return -EAGAIN;
			kvm_cache_gfn_to_pfn(slot, gfn, cache, gen);
		}
		pfn = cache->pfn;
	} else {
		if (atomic)
			return -EAGAIN;
		pfn = gfn_to_pfn_memslot(slot, gfn);
	}
1874 1875 1876 1877 1878
	if (is_error_noslot_pfn(pfn))
		return -EINVAL;

	if (pfn_valid(pfn)) {
		page = pfn_to_page(pfn);
1879 1880 1881 1882
		if (atomic)
			hva = kmap_atomic(page);
		else
			hva = kmap(page);
P
Paolo Bonzini 已提交
1883
#ifdef CONFIG_HAS_IOMEM
1884
	} else if (!atomic) {
1885
		hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
1886 1887
	} else {
		return -EINVAL;
P
Paolo Bonzini 已提交
1888
#endif
1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901
	}

	if (!hva)
		return -EFAULT;

	map->page = page;
	map->hva = hva;
	map->pfn = pfn;
	map->gfn = gfn;

	return 0;
}

1902 1903
int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map,
		struct gfn_to_pfn_cache *cache, bool atomic)
1904
{
1905 1906
	return __kvm_map_gfn(kvm_memslots(vcpu->kvm), gfn, map,
			cache, atomic);
1907 1908 1909
}
EXPORT_SYMBOL_GPL(kvm_map_gfn);

1910 1911
int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
{
1912 1913
	return __kvm_map_gfn(kvm_vcpu_memslots(vcpu), gfn, map,
		NULL, false);
1914 1915 1916
}
EXPORT_SYMBOL_GPL(kvm_vcpu_map);

1917
static void __kvm_unmap_gfn(struct kvm_memory_slot *memslot,
1918 1919 1920
			struct kvm_host_map *map,
			struct gfn_to_pfn_cache *cache,
			bool dirty, bool atomic)
1921 1922 1923 1924 1925 1926 1927
{
	if (!map)
		return;

	if (!map->hva)
		return;

1928 1929 1930 1931 1932 1933
	if (map->page != KVM_UNMAPPED_PAGE) {
		if (atomic)
			kunmap_atomic(map->hva);
		else
			kunmap(map->page);
	}
1934
#ifdef CONFIG_HAS_IOMEM
1935
	else if (!atomic)
1936
		memunmap(map->hva);
1937 1938
	else
		WARN_ONCE(1, "Unexpected unmapping in atomic context");
1939
#endif
1940

1941
	if (dirty)
1942
		mark_page_dirty_in_slot(memslot, map->gfn);
1943 1944 1945 1946 1947

	if (cache)
		cache->dirty |= dirty;
	else
		kvm_release_pfn(map->pfn, dirty, NULL);
1948 1949 1950 1951

	map->hva = NULL;
	map->page = NULL;
}
1952

1953 1954
int kvm_unmap_gfn(struct kvm_vcpu *vcpu, struct kvm_host_map *map, 
		  struct gfn_to_pfn_cache *cache, bool dirty, bool atomic)
1955
{
1956 1957
	__kvm_unmap_gfn(gfn_to_memslot(vcpu->kvm, map->gfn), map,
			cache, dirty, atomic);
1958 1959 1960 1961 1962 1963
	return 0;
}
EXPORT_SYMBOL_GPL(kvm_unmap_gfn);

void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
{
1964 1965
	__kvm_unmap_gfn(kvm_vcpu_gfn_to_memslot(vcpu, map->gfn), map, NULL,
			dirty, false);
1966
}
1967 1968
EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);

1969 1970
struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
{
D
Dan Williams 已提交
1971
	kvm_pfn_t pfn;
1972 1973 1974 1975 1976 1977 1978

	pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn);

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

1979 1980
void kvm_release_page_clean(struct page *page)
{
1981 1982
	WARN_ON(is_error_page(page));

1983
	kvm_release_pfn_clean(page_to_pfn(page));
1984 1985 1986
}
EXPORT_SYMBOL_GPL(kvm_release_page_clean);

D
Dan Williams 已提交
1987
void kvm_release_pfn_clean(kvm_pfn_t pfn)
1988
{
1989
	if (!is_error_noslot_pfn(pfn) && !kvm_is_reserved_pfn(pfn))
1990
		put_page(pfn_to_page(pfn));
1991 1992 1993
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);

1994
void kvm_release_page_dirty(struct page *page)
1995
{
X
Xiao Guangrong 已提交
1996 1997
	WARN_ON(is_error_page(page));

1998 1999 2000 2001
	kvm_release_pfn_dirty(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_dirty);

2002
void kvm_release_pfn_dirty(kvm_pfn_t pfn)
2003 2004 2005 2006
{
	kvm_set_pfn_dirty(pfn);
	kvm_release_pfn_clean(pfn);
}
2007
EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
2008

D
Dan Williams 已提交
2009
void kvm_set_pfn_dirty(kvm_pfn_t pfn)
2010
{
2011 2012
	if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
		SetPageDirty(pfn_to_page(pfn));
2013
}
2014 2015
EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);

D
Dan Williams 已提交
2016
void kvm_set_pfn_accessed(kvm_pfn_t pfn)
2017
{
2018
	if (!kvm_is_reserved_pfn(pfn) && !kvm_is_zone_device_pfn(pfn))
2019
		mark_page_accessed(pfn_to_page(pfn));
2020 2021 2022
}
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);

D
Dan Williams 已提交
2023
void kvm_get_pfn(kvm_pfn_t pfn)
2024
{
2025
	if (!kvm_is_reserved_pfn(pfn))
2026
		get_page(pfn_to_page(pfn));
2027 2028
}
EXPORT_SYMBOL_GPL(kvm_get_pfn);
2029

2030 2031 2032 2033 2034 2035 2036 2037
static int next_segment(unsigned long len, int offset)
{
	if (len > PAGE_SIZE - offset)
		return PAGE_SIZE - offset;
	else
		return len;
}

2038 2039
static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
				 void *data, int offset, int len)
2040
{
2041 2042
	int r;
	unsigned long addr;
2043

2044
	addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
2045 2046
	if (kvm_is_error_hva(addr))
		return -EFAULT;
2047
	r = __copy_from_user(data, (void __user *)addr + offset, len);
2048
	if (r)
2049 2050 2051
		return -EFAULT;
	return 0;
}
2052 2053 2054 2055 2056 2057 2058 2059

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);
}
2060 2061
EXPORT_SYMBOL_GPL(kvm_read_guest_page);

2062 2063 2064 2065 2066 2067 2068 2069 2070
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);

2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090
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);

2091
int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
2092 2093
{
	gfn_t gfn = gpa >> PAGE_SHIFT;
2094
	int seg;
2095
	int offset = offset_in_page(gpa);
2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109
	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);
2110

2111 2112 2113 2114 2115 2116 2117
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);
2118 2119
	if (kvm_is_error_hva(addr))
		return -EFAULT;
2120
	pagefault_disable();
2121
	r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
2122
	pagefault_enable();
2123 2124 2125 2126 2127
	if (r)
		return -EFAULT;
	return 0;
}

2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140
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)
2141
{
2142 2143
	int r;
	unsigned long addr;
2144

2145
	addr = gfn_to_hva_memslot(memslot, gfn);
2146 2147
	if (kvm_is_error_hva(addr))
		return -EFAULT;
2148
	r = __copy_to_user((void __user *)addr + offset, data, len);
2149
	if (r)
2150
		return -EFAULT;
2151
	mark_page_dirty_in_slot(memslot, gfn);
2152 2153
	return 0;
}
2154 2155 2156 2157 2158 2159 2160 2161

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);
}
2162 2163
EXPORT_SYMBOL_GPL(kvm_write_guest_page);

2164 2165 2166 2167 2168 2169 2170 2171 2172
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);

2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191
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;
}
2192
EXPORT_SYMBOL_GPL(kvm_write_guest);
2193

2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214
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);

2215 2216 2217
static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
				       struct gfn_to_hva_cache *ghc,
				       gpa_t gpa, unsigned long len)
2218 2219
{
	int offset = offset_in_page(gpa);
2220 2221 2222 2223
	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;
2224

2225
	/* Update ghc->generation before performing any error checks. */
2226
	ghc->generation = slots->generation;
2227 2228 2229 2230 2231

	if (start_gfn > end_gfn) {
		ghc->hva = KVM_HVA_ERR_BAD;
		return -EINVAL;
	}
2232 2233 2234 2235 2236

	/*
	 * If the requested region crosses two memslots, we still
	 * verify that the entire region is valid here.
	 */
2237
	for ( ; start_gfn <= end_gfn; start_gfn += nr_pages_avail) {
2238 2239 2240 2241
		ghc->memslot = __gfn_to_memslot(slots, start_gfn);
		ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
					   &nr_pages_avail);
		if (kvm_is_error_hva(ghc->hva))
2242
			return -EFAULT;
2243 2244 2245
	}

	/* Use the slow path for cross page reads and writes. */
2246
	if (nr_pages_needed == 1)
2247
		ghc->hva += offset;
2248
	else
2249
		ghc->memslot = NULL;
2250

2251 2252 2253
	ghc->gpa = gpa;
	ghc->len = len;
	return 0;
2254
}
2255

2256
int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2257 2258
			      gpa_t gpa, unsigned long len)
{
2259
	struct kvm_memslots *slots = kvm_memslots(kvm);
2260 2261
	return __kvm_gfn_to_hva_cache_init(slots, ghc, gpa, len);
}
2262
EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
2263

2264
int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
2265 2266
				  void *data, unsigned int offset,
				  unsigned long len)
2267
{
2268
	struct kvm_memslots *slots = kvm_memslots(kvm);
2269
	int r;
2270
	gpa_t gpa = ghc->gpa + offset;
2271

2272
	BUG_ON(len + offset > ghc->len);
2273

2274 2275 2276 2277
	if (slots->generation != ghc->generation) {
		if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
			return -EFAULT;
	}
2278

2279 2280 2281
	if (kvm_is_error_hva(ghc->hva))
		return -EFAULT;

2282 2283 2284
	if (unlikely(!ghc->memslot))
		return kvm_write_guest(kvm, gpa, data, len);

2285
	r = __copy_to_user((void __user *)ghc->hva + offset, data, len);
2286 2287
	if (r)
		return -EFAULT;
2288
	mark_page_dirty_in_slot(ghc->memslot, gpa >> PAGE_SHIFT);
2289 2290 2291

	return 0;
}
2292
EXPORT_SYMBOL_GPL(kvm_write_guest_offset_cached);
2293

2294 2295
int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
			   void *data, unsigned long len)
2296
{
2297
	return kvm_write_guest_offset_cached(kvm, ghc, data, 0, len);
2298
}
2299
EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
2300

2301 2302
int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
			   void *data, unsigned long len)
2303
{
2304
	struct kvm_memslots *slots = kvm_memslots(kvm);
2305 2306
	int r;

2307 2308
	BUG_ON(len > ghc->len);

2309 2310 2311 2312
	if (slots->generation != ghc->generation) {
		if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
			return -EFAULT;
	}
2313

2314 2315 2316
	if (kvm_is_error_hva(ghc->hva))
		return -EFAULT;

2317 2318 2319
	if (unlikely(!ghc->memslot))
		return kvm_read_guest(kvm, ghc->gpa, data, len);

2320 2321 2322 2323 2324 2325
	r = __copy_from_user(data, (void __user *)ghc->hva, len);
	if (r)
		return -EFAULT;

	return 0;
}
2326
EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
2327

2328 2329
int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
{
2330 2331 2332
	const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));

	return kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
2333 2334 2335 2336 2337 2338 2339 2340 2341 2342
}
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;

2343
	while ((seg = next_segment(len, offset)) != 0) {
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354
		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);

2355
static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
2356
				    gfn_t gfn)
A
Avi Kivity 已提交
2357
{
R
Rusty Russell 已提交
2358 2359
	if (memslot && memslot->dirty_bitmap) {
		unsigned long rel_gfn = gfn - memslot->base_gfn;
A
Avi Kivity 已提交
2360

2361
		set_bit_le(rel_gfn, memslot->dirty_bitmap);
A
Avi Kivity 已提交
2362 2363 2364
	}
}

2365 2366 2367 2368 2369
void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
{
	struct kvm_memory_slot *memslot;

	memslot = gfn_to_memslot(kvm, gfn);
2370
	mark_page_dirty_in_slot(memslot, gfn);
2371
}
2372
EXPORT_SYMBOL_GPL(mark_page_dirty);
2373

2374 2375 2376 2377 2378 2379 2380 2381 2382
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);

2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405
void kvm_sigset_activate(struct kvm_vcpu *vcpu)
{
	if (!vcpu->sigset_active)
		return;

	/*
	 * This does a lockless modification of ->real_blocked, which is fine
	 * because, only current can change ->real_blocked and all readers of
	 * ->real_blocked don't care as long ->real_blocked is always a subset
	 * of ->blocked.
	 */
	sigprocmask(SIG_SETMASK, &vcpu->sigset, &current->real_blocked);
}

void kvm_sigset_deactivate(struct kvm_vcpu *vcpu)
{
	if (!vcpu->sigset_active)
		return;

	sigprocmask(SIG_SETMASK, &current->real_blocked, NULL);
	sigemptyset(&current->real_blocked);
}

W
Wanpeng Li 已提交
2406 2407
static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
{
2408
	unsigned int old, val, grow, grow_start;
W
Wanpeng Li 已提交
2409

2410
	old = val = vcpu->halt_poll_ns;
2411
	grow_start = READ_ONCE(halt_poll_ns_grow_start);
2412
	grow = READ_ONCE(halt_poll_ns_grow);
2413 2414 2415
	if (!grow)
		goto out;

2416 2417 2418
	val *= grow;
	if (val < grow_start)
		val = grow_start;
W
Wanpeng Li 已提交
2419

2420 2421 2422
	if (val > halt_poll_ns)
		val = halt_poll_ns;

W
Wanpeng Li 已提交
2423
	vcpu->halt_poll_ns = val;
2424
out:
2425
	trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
W
Wanpeng Li 已提交
2426 2427 2428 2429
}

static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
{
2430
	unsigned int old, val, shrink;
W
Wanpeng Li 已提交
2431

2432
	old = val = vcpu->halt_poll_ns;
2433 2434
	shrink = READ_ONCE(halt_poll_ns_shrink);
	if (shrink == 0)
W
Wanpeng Li 已提交
2435 2436
		val = 0;
	else
2437
		val /= shrink;
W
Wanpeng Li 已提交
2438 2439

	vcpu->halt_poll_ns = val;
2440
	trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
W
Wanpeng Li 已提交
2441 2442
}

2443 2444
static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
{
2445 2446 2447
	int ret = -EINTR;
	int idx = srcu_read_lock(&vcpu->kvm->srcu);

2448 2449
	if (kvm_arch_vcpu_runnable(vcpu)) {
		kvm_make_request(KVM_REQ_UNHALT, vcpu);
2450
		goto out;
2451 2452
	}
	if (kvm_cpu_has_pending_timer(vcpu))
2453
		goto out;
2454
	if (signal_pending(current))
2455
		goto out;
2456

2457 2458 2459 2460
	ret = 0;
out:
	srcu_read_unlock(&vcpu->kvm->srcu, idx);
	return ret;
2461 2462
}

E
Eddie Dong 已提交
2463 2464 2465
/*
 * The vCPU has executed a HLT instruction with in-kernel mode enabled.
 */
2466
void kvm_vcpu_block(struct kvm_vcpu *vcpu)
2467
{
2468
	ktime_t start, cur;
2469
	DECLARE_SWAITQUEUE(wait);
2470
	bool waited = false;
W
Wanpeng Li 已提交
2471
	u64 block_ns;
2472

2473 2474
	kvm_arch_vcpu_blocking(vcpu);

2475
	start = cur = ktime_get();
2476
	if (vcpu->halt_poll_ns && !kvm_arch_no_poll(vcpu)) {
W
Wanpeng Li 已提交
2477
		ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
2478

2479
		++vcpu->stat.halt_attempted_poll;
2480 2481 2482 2483 2484 2485 2486
		do {
			/*
			 * This sets KVM_REQ_UNHALT if an interrupt
			 * arrives.
			 */
			if (kvm_vcpu_check_block(vcpu) < 0) {
				++vcpu->stat.halt_successful_poll;
2487 2488
				if (!vcpu_valid_wakeup(vcpu))
					++vcpu->stat.halt_poll_invalid;
2489 2490 2491 2492 2493
				goto out;
			}
			cur = ktime_get();
		} while (single_task_running() && ktime_before(cur, stop));
	}
2494 2495

	for (;;) {
2496
		prepare_to_swait_exclusive(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
2497

2498
		if (kvm_vcpu_check_block(vcpu) < 0)
2499 2500
			break;

2501
		waited = true;
E
Eddie Dong 已提交
2502 2503
		schedule();
	}
2504

2505
	finish_swait(&vcpu->wq, &wait);
2506 2507
	cur = ktime_get();
out:
2508
	kvm_arch_vcpu_unblocking(vcpu);
W
Wanpeng Li 已提交
2509 2510
	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);

2511 2512
	if (!kvm_arch_no_poll(vcpu)) {
		if (!vcpu_valid_wakeup(vcpu)) {
W
Wanpeng Li 已提交
2513
			shrink_halt_poll_ns(vcpu);
2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527
		} else if (halt_poll_ns) {
			if (block_ns <= vcpu->halt_poll_ns)
				;
			/* we had a long block, shrink polling */
			else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns)
				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);
		} else {
			vcpu->halt_poll_ns = 0;
		}
	}
W
Wanpeng Li 已提交
2528

2529 2530
	trace_kvm_vcpu_wakeup(block_ns, waited, vcpu_valid_wakeup(vcpu));
	kvm_arch_vcpu_block_finish(vcpu);
E
Eddie Dong 已提交
2531
}
2532
EXPORT_SYMBOL_GPL(kvm_vcpu_block);
E
Eddie Dong 已提交
2533

2534
bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
2535
{
2536
	struct swait_queue_head *wqp;
2537 2538

	wqp = kvm_arch_vcpu_wq(vcpu);
2539
	if (swq_has_sleeper(wqp)) {
2540
		swake_up_one(wqp);
2541
		WRITE_ONCE(vcpu->ready, true);
2542
		++vcpu->stat.halt_wakeup;
2543
		return true;
2544 2545
	}

2546
	return false;
2547 2548 2549
}
EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);

2550
#ifndef CONFIG_S390
2551 2552 2553 2554 2555 2556 2557 2558
/*
 * 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;

2559 2560 2561
	if (kvm_vcpu_wake_up(vcpu))
		return;

2562 2563 2564 2565 2566 2567
	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();
}
2568
EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
2569
#endif /* !CONFIG_S390 */
2570

2571
int kvm_vcpu_yield_to(struct kvm_vcpu *target)
2572 2573 2574
{
	struct pid *pid;
	struct task_struct *task = NULL;
2575
	int ret = 0;
2576 2577 2578 2579

	rcu_read_lock();
	pid = rcu_dereference(target->pid);
	if (pid)
2580
		task = get_pid_task(pid, PIDTYPE_PID);
2581 2582
	rcu_read_unlock();
	if (!task)
2583 2584
		return ret;
	ret = yield_to(task, 1);
2585
	put_task_struct(task);
2586 2587

	return ret;
2588 2589 2590
}
EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);

2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612
/*
 * 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.
 */
2613
static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
2614
{
2615
#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
2616 2617 2618
	bool eligible;

	eligible = !vcpu->spin_loop.in_spin_loop ||
2619
		    vcpu->spin_loop.dy_eligible;
2620 2621 2622 2623 2624

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

	return eligible;
2625 2626
#else
	return true;
2627
#endif
2628
}
2629

2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652
/*
 * Unlike kvm_arch_vcpu_runnable, this function is called outside
 * a vcpu_load/vcpu_put pair.  However, for most architectures
 * kvm_arch_vcpu_runnable does not require vcpu_load.
 */
bool __weak kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
{
	return kvm_arch_vcpu_runnable(vcpu);
}

static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu)
{
	if (kvm_arch_dy_runnable(vcpu))
		return true;

#ifdef CONFIG_KVM_ASYNC_PF
	if (!list_empty_careful(&vcpu->async_pf.done))
		return true;
#endif

	return false;
}

2653
void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
Z
Zhai, Edwin 已提交
2654
{
2655 2656 2657 2658
	struct kvm *kvm = me->kvm;
	struct kvm_vcpu *vcpu;
	int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
	int yielded = 0;
2659
	int try = 3;
2660 2661
	int pass;
	int i;
Z
Zhai, Edwin 已提交
2662

2663
	kvm_vcpu_set_in_spin_loop(me, true);
2664 2665 2666 2667 2668 2669 2670
	/*
	 * 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.
	 */
2671
	for (pass = 0; pass < 2 && !yielded && try; pass++) {
2672
		kvm_for_each_vcpu(i, vcpu, kvm) {
2673
			if (!pass && i <= last_boosted_vcpu) {
2674 2675 2676 2677
				i = last_boosted_vcpu;
				continue;
			} else if (pass && i > last_boosted_vcpu)
				break;
2678
			if (!READ_ONCE(vcpu->ready))
2679
				continue;
2680 2681
			if (vcpu == me)
				continue;
2682
			if (swait_active(&vcpu->wq) && !vcpu_dy_runnable(vcpu))
2683
				continue;
2684 2685
			if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode &&
				!kvm_arch_vcpu_in_kernel(vcpu))
2686
				continue;
2687 2688
			if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
				continue;
2689 2690 2691

			yielded = kvm_vcpu_yield_to(vcpu);
			if (yielded > 0) {
2692 2693
				kvm->last_boosted_vcpu = i;
				break;
2694 2695 2696 2697
			} else if (yielded < 0) {
				try--;
				if (!try)
					break;
2698 2699 2700
			}
		}
	}
2701
	kvm_vcpu_set_in_spin_loop(me, false);
2702 2703 2704

	/* Ensure vcpu is not eligible during next spinloop */
	kvm_vcpu_set_dy_eligible(me, false);
Z
Zhai, Edwin 已提交
2705 2706 2707
}
EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);

2708
static vm_fault_t kvm_vcpu_fault(struct vm_fault *vmf)
2709
{
2710
	struct kvm_vcpu *vcpu = vmf->vma->vm_file->private_data;
2711 2712
	struct page *page;

2713
	if (vmf->pgoff == 0)
2714
		page = virt_to_page(vcpu->run);
A
Avi Kivity 已提交
2715
#ifdef CONFIG_X86
2716
	else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
2717
		page = virt_to_page(vcpu->arch.pio_data);
2718
#endif
2719
#ifdef CONFIG_KVM_MMIO
2720 2721
	else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
		page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
A
Avi Kivity 已提交
2722
#endif
2723
	else
2724
		return kvm_arch_vcpu_fault(vcpu, vmf);
2725
	get_page(page);
2726 2727
	vmf->page = page;
	return 0;
2728 2729
}

2730
static const struct vm_operations_struct kvm_vcpu_vm_ops = {
2731
	.fault = kvm_vcpu_fault,
2732 2733 2734 2735 2736 2737 2738 2739
};

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
2740 2741 2742 2743
static int kvm_vcpu_release(struct inode *inode, struct file *filp)
{
	struct kvm_vcpu *vcpu = filp->private_data;

2744
	debugfs_remove_recursive(vcpu->debugfs_dentry);
A
Al Viro 已提交
2745
	kvm_put_kvm(vcpu->kvm);
A
Avi Kivity 已提交
2746 2747 2748
	return 0;
}

2749
static struct file_operations kvm_vcpu_fops = {
A
Avi Kivity 已提交
2750 2751
	.release        = kvm_vcpu_release,
	.unlocked_ioctl = kvm_vcpu_ioctl,
2752
	.mmap           = kvm_vcpu_mmap,
2753
	.llseek		= noop_llseek,
2754
	KVM_COMPAT(kvm_vcpu_compat_ioctl),
A
Avi Kivity 已提交
2755 2756 2757 2758 2759 2760 2761
};

/*
 * Allocates an inode for the vcpu.
 */
static int create_vcpu_fd(struct kvm_vcpu *vcpu)
{
2762 2763 2764 2765
	char name[8 + 1 + ITOA_MAX_LEN + 1];

	snprintf(name, sizeof(name), "kvm-vcpu:%d", vcpu->vcpu_id);
	return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
A
Avi Kivity 已提交
2766 2767
}

2768
static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
2769
{
2770
#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
2771 2772 2773
	char dir_name[ITOA_MAX_LEN * 2];

	if (!debugfs_initialized())
2774
		return;
2775 2776 2777

	snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
	vcpu->debugfs_dentry = debugfs_create_dir(dir_name,
2778
						  vcpu->kvm->debugfs_dentry);
2779

2780
	kvm_arch_create_vcpu_debugfs(vcpu);
2781
#endif
2782 2783
}

2784 2785 2786
/*
 * Creates some virtual cpus.  Good luck creating more than one.
 */
2787
static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
2788 2789
{
	int r;
2790
	struct kvm_vcpu *vcpu;
2791
	struct page *page;
2792

G
Greg Kurz 已提交
2793
	if (id >= KVM_MAX_VCPU_ID)
2794 2795
		return -EINVAL;

2796 2797 2798 2799 2800 2801 2802 2803 2804
	mutex_lock(&kvm->lock);
	if (kvm->created_vcpus == KVM_MAX_VCPUS) {
		mutex_unlock(&kvm->lock);
		return -EINVAL;
	}

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

2805 2806 2807 2808
	r = kvm_arch_vcpu_precreate(kvm, id);
	if (r)
		goto vcpu_decrement;

2809 2810 2811
	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
	if (!vcpu) {
		r = -ENOMEM;
2812 2813
		goto vcpu_decrement;
	}
2814

2815
	BUILD_BUG_ON(sizeof(struct kvm_run) > PAGE_SIZE);
2816 2817 2818
	page = alloc_page(GFP_KERNEL | __GFP_ZERO);
	if (!page) {
		r = -ENOMEM;
2819
		goto vcpu_free;
2820 2821 2822 2823
	}
	vcpu->run = page_address(page);

	kvm_vcpu_init(vcpu, kvm, id);
2824 2825 2826

	r = kvm_arch_vcpu_create(vcpu);
	if (r)
2827
		goto vcpu_free_run_page;
2828

2829
	kvm_create_vcpu_debugfs(vcpu);
2830

S
Shaohua Li 已提交
2831
	mutex_lock(&kvm->lock);
2832 2833 2834 2835
	if (kvm_get_vcpu_by_id(kvm, id)) {
		r = -EEXIST;
		goto unlock_vcpu_destroy;
	}
2836

2837 2838
	vcpu->vcpu_idx = atomic_read(&kvm->online_vcpus);
	BUG_ON(kvm->vcpus[vcpu->vcpu_idx]);
2839

R
Rusty Russell 已提交
2840
	/* Now it's all set up, let userspace reach it */
A
Al Viro 已提交
2841
	kvm_get_kvm(kvm);
A
Avi Kivity 已提交
2842
	r = create_vcpu_fd(vcpu);
2843
	if (r < 0) {
2844
		kvm_put_kvm_no_destroy(kvm);
2845
		goto unlock_vcpu_destroy;
2846 2847
	}

2848
	kvm->vcpus[vcpu->vcpu_idx] = vcpu;
2849 2850 2851 2852 2853

	/*
	 * Pairs with smp_rmb() in kvm_get_vcpu.  Write kvm->vcpus
	 * before kvm->online_vcpu's incremented value.
	 */
2854 2855 2856 2857
	smp_wmb();
	atomic_inc(&kvm->online_vcpus);

	mutex_unlock(&kvm->lock);
2858
	kvm_arch_vcpu_postcreate(vcpu);
R
Rusty Russell 已提交
2859
	return r;
2860

2861
unlock_vcpu_destroy:
2862
	mutex_unlock(&kvm->lock);
2863
	debugfs_remove_recursive(vcpu->debugfs_dentry);
2864
	kvm_arch_vcpu_destroy(vcpu);
2865 2866
vcpu_free_run_page:
	free_page((unsigned long)vcpu->run);
2867 2868
vcpu_free:
	kmem_cache_free(kvm_vcpu_cache, vcpu);
2869 2870 2871 2872
vcpu_decrement:
	mutex_lock(&kvm->lock);
	kvm->created_vcpus--;
	mutex_unlock(&kvm->lock);
2873 2874 2875
	return r;
}

A
Avi Kivity 已提交
2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886
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
2887 2888
static long kvm_vcpu_ioctl(struct file *filp,
			   unsigned int ioctl, unsigned long arg)
A
Avi Kivity 已提交
2889
{
A
Avi Kivity 已提交
2890
	struct kvm_vcpu *vcpu = filp->private_data;
A
Al Viro 已提交
2891
	void __user *argp = (void __user *)arg;
2892
	int r;
2893 2894
	struct kvm_fpu *fpu = NULL;
	struct kvm_sregs *kvm_sregs = NULL;
A
Avi Kivity 已提交
2895

2896 2897
	if (vcpu->kvm->mm != current->mm)
		return -EIO;
2898

2899 2900 2901
	if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
		return -EINVAL;

2902
	/*
2903 2904
	 * Some architectures have vcpu ioctls that are asynchronous to vcpu
	 * execution; mutex_lock() would break them.
2905
	 */
2906 2907
	r = kvm_arch_vcpu_async_ioctl(filp, ioctl, arg);
	if (r != -ENOIOCTLCMD)
2908
		return r;
2909

2910 2911
	if (mutex_lock_killable(&vcpu->mutex))
		return -EINTR;
A
Avi Kivity 已提交
2912
	switch (ioctl) {
2913 2914
	case KVM_RUN: {
		struct pid *oldpid;
2915 2916 2917
		r = -EINVAL;
		if (arg)
			goto out;
2918
		oldpid = rcu_access_pointer(vcpu->pid);
2919
		if (unlikely(oldpid != task_pid(current))) {
2920
			/* The thread running this VCPU changed. */
2921
			struct pid *newpid;
2922

2923 2924 2925 2926 2927
			r = kvm_arch_vcpu_run_pid_change(vcpu);
			if (r)
				break;

			newpid = get_task_pid(current, PIDTYPE_PID);
2928 2929 2930 2931 2932
			rcu_assign_pointer(vcpu->pid, newpid);
			if (oldpid)
				synchronize_rcu();
			put_pid(oldpid);
		}
2933
		r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
2934
		trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
A
Avi Kivity 已提交
2935
		break;
2936
	}
A
Avi Kivity 已提交
2937
	case KVM_GET_REGS: {
2938
		struct kvm_regs *kvm_regs;
A
Avi Kivity 已提交
2939

2940
		r = -ENOMEM;
2941
		kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL_ACCOUNT);
2942
		if (!kvm_regs)
A
Avi Kivity 已提交
2943
			goto out;
2944 2945 2946
		r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
		if (r)
			goto out_free1;
A
Avi Kivity 已提交
2947
		r = -EFAULT;
2948 2949
		if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
			goto out_free1;
A
Avi Kivity 已提交
2950
		r = 0;
2951 2952
out_free1:
		kfree(kvm_regs);
A
Avi Kivity 已提交
2953 2954 2955
		break;
	}
	case KVM_SET_REGS: {
2956
		struct kvm_regs *kvm_regs;
A
Avi Kivity 已提交
2957

2958
		r = -ENOMEM;
2959 2960 2961
		kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
		if (IS_ERR(kvm_regs)) {
			r = PTR_ERR(kvm_regs);
A
Avi Kivity 已提交
2962
			goto out;
2963
		}
2964 2965
		r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
		kfree(kvm_regs);
A
Avi Kivity 已提交
2966 2967 2968
		break;
	}
	case KVM_GET_SREGS: {
2969 2970
		kvm_sregs = kzalloc(sizeof(struct kvm_sregs),
				    GFP_KERNEL_ACCOUNT);
2971 2972 2973 2974
		r = -ENOMEM;
		if (!kvm_sregs)
			goto out;
		r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
A
Avi Kivity 已提交
2975 2976 2977
		if (r)
			goto out;
		r = -EFAULT;
2978
		if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
A
Avi Kivity 已提交
2979 2980 2981 2982 2983
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_SREGS: {
2984 2985 2986
		kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
		if (IS_ERR(kvm_sregs)) {
			r = PTR_ERR(kvm_sregs);
G
Guo Chao 已提交
2987
			kvm_sregs = NULL;
A
Avi Kivity 已提交
2988
			goto out;
2989
		}
2990
		r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
A
Avi Kivity 已提交
2991 2992
		break;
	}
2993 2994 2995 2996 2997 2998 2999
	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;
3000
		if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
3001 3002 3003 3004 3005 3006 3007 3008
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_MP_STATE: {
		struct kvm_mp_state mp_state;

		r = -EFAULT;
3009
		if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
3010 3011 3012 3013
			goto out;
		r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
		break;
	}
A
Avi Kivity 已提交
3014 3015 3016 3017
	case KVM_TRANSLATE: {
		struct kvm_translation tr;

		r = -EFAULT;
3018
		if (copy_from_user(&tr, argp, sizeof(tr)))
A
Avi Kivity 已提交
3019
			goto out;
3020
		r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
A
Avi Kivity 已提交
3021 3022 3023
		if (r)
			goto out;
		r = -EFAULT;
3024
		if (copy_to_user(argp, &tr, sizeof(tr)))
A
Avi Kivity 已提交
3025 3026 3027 3028
			goto out;
		r = 0;
		break;
	}
J
Jan Kiszka 已提交
3029 3030
	case KVM_SET_GUEST_DEBUG: {
		struct kvm_guest_debug dbg;
A
Avi Kivity 已提交
3031 3032

		r = -EFAULT;
3033
		if (copy_from_user(&dbg, argp, sizeof(dbg)))
A
Avi Kivity 已提交
3034
			goto out;
J
Jan Kiszka 已提交
3035
		r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
A
Avi Kivity 已提交
3036 3037
		break;
	}
A
Avi Kivity 已提交
3038 3039 3040 3041 3042 3043 3044 3045 3046
	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,
3047
					   sizeof(kvm_sigmask)))
A
Avi Kivity 已提交
3048 3049
				goto out;
			r = -EINVAL;
3050
			if (kvm_sigmask.len != sizeof(sigset))
A
Avi Kivity 已提交
3051 3052 3053
				goto out;
			r = -EFAULT;
			if (copy_from_user(&sigset, sigmask_arg->sigset,
3054
					   sizeof(sigset)))
A
Avi Kivity 已提交
3055 3056 3057
				goto out;
			p = &sigset;
		}
3058
		r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
A
Avi Kivity 已提交
3059 3060
		break;
	}
A
Avi Kivity 已提交
3061
	case KVM_GET_FPU: {
3062
		fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL_ACCOUNT);
3063 3064 3065 3066
		r = -ENOMEM;
		if (!fpu)
			goto out;
		r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
A
Avi Kivity 已提交
3067 3068 3069
		if (r)
			goto out;
		r = -EFAULT;
3070
		if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
A
Avi Kivity 已提交
3071 3072 3073 3074 3075
			goto out;
		r = 0;
		break;
	}
	case KVM_SET_FPU: {
3076 3077 3078
		fpu = memdup_user(argp, sizeof(*fpu));
		if (IS_ERR(fpu)) {
			r = PTR_ERR(fpu);
G
Guo Chao 已提交
3079
			fpu = NULL;
A
Avi Kivity 已提交
3080
			goto out;
3081
		}
3082
		r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
A
Avi Kivity 已提交
3083 3084
		break;
	}
A
Avi Kivity 已提交
3085
	default:
3086
		r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
A
Avi Kivity 已提交
3087 3088
	}
out:
3089
	mutex_unlock(&vcpu->mutex);
3090 3091
	kfree(fpu);
	kfree(kvm_sregs);
A
Avi Kivity 已提交
3092 3093 3094
	return r;
}

3095
#ifdef CONFIG_KVM_COMPAT
3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114
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;
		sigset_t sigset;

		if (argp) {
			r = -EFAULT;
			if (copy_from_user(&kvm_sigmask, argp,
3115
					   sizeof(kvm_sigmask)))
3116 3117
				goto out;
			r = -EINVAL;
A
Al Viro 已提交
3118
			if (kvm_sigmask.len != sizeof(compat_sigset_t))
3119 3120
				goto out;
			r = -EFAULT;
A
Al Viro 已提交
3121
			if (get_compat_sigset(&sigset, (void *)sigmask_arg->sigset))
3122
				goto out;
3123 3124 3125
			r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
		} else
			r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136
		break;
	}
	default:
		r = kvm_vcpu_ioctl(filp, ioctl, arg);
	}

out:
	return r;
}
#endif

3137 3138 3139 3140 3141 3142 3143 3144 3145 3146
static int kvm_device_mmap(struct file *filp, struct vm_area_struct *vma)
{
	struct kvm_device *dev = filp->private_data;

	if (dev->ops->mmap)
		return dev->ops->mmap(dev, vma);

	return -ENODEV;
}

S
Scott Wood 已提交
3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167
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;

3168 3169 3170
	if (dev->kvm->mm != current->mm)
		return -EIO;

S
Scott Wood 已提交
3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190
	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;

3191 3192 3193 3194 3195 3196 3197
	if (dev->ops->release) {
		mutex_lock(&kvm->lock);
		list_del(&dev->vm_node);
		dev->ops->release(dev);
		mutex_unlock(&kvm->lock);
	}

S
Scott Wood 已提交
3198 3199 3200 3201 3202 3203 3204
	kvm_put_kvm(kvm);
	return 0;
}

static const struct file_operations kvm_device_fops = {
	.unlocked_ioctl = kvm_device_ioctl,
	.release = kvm_device_release,
3205
	KVM_COMPAT(kvm_device_ioctl),
3206
	.mmap = kvm_device_mmap,
S
Scott Wood 已提交
3207 3208 3209 3210 3211 3212 3213 3214 3215 3216
};

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

	return filp->private_data;
}

3217
static const struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
3218
#ifdef CONFIG_KVM_MPIC
3219 3220
	[KVM_DEV_TYPE_FSL_MPIC_20]	= &kvm_mpic_ops,
	[KVM_DEV_TYPE_FSL_MPIC_42]	= &kvm_mpic_ops,
3221
#endif
3222 3223
};

3224
int kvm_register_device_ops(const struct kvm_device_ops *ops, u32 type)
3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235
{
	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;
}

3236 3237 3238 3239 3240 3241
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
3242 3243 3244
static int kvm_ioctl_create_device(struct kvm *kvm,
				   struct kvm_create_device *cd)
{
3245
	const struct kvm_device_ops *ops = NULL;
S
Scott Wood 已提交
3246 3247
	struct kvm_device *dev;
	bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
P
Paolo Bonzini 已提交
3248
	int type;
S
Scott Wood 已提交
3249 3250
	int ret;

3251 3252 3253
	if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
		return -ENODEV;

P
Paolo Bonzini 已提交
3254 3255
	type = array_index_nospec(cd->type, ARRAY_SIZE(kvm_device_ops_table));
	ops = kvm_device_ops_table[type];
3256
	if (ops == NULL)
S
Scott Wood 已提交
3257 3258 3259 3260 3261
		return -ENODEV;

	if (test)
		return 0;

3262
	dev = kzalloc(sizeof(*dev), GFP_KERNEL_ACCOUNT);
S
Scott Wood 已提交
3263 3264 3265 3266 3267 3268
	if (!dev)
		return -ENOMEM;

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

3269
	mutex_lock(&kvm->lock);
P
Paolo Bonzini 已提交
3270
	ret = ops->create(dev, type);
S
Scott Wood 已提交
3271
	if (ret < 0) {
3272
		mutex_unlock(&kvm->lock);
S
Scott Wood 已提交
3273 3274 3275
		kfree(dev);
		return ret;
	}
3276 3277
	list_add(&dev->vm_node, &kvm->devices);
	mutex_unlock(&kvm->lock);
S
Scott Wood 已提交
3278

3279 3280 3281
	if (ops->init)
		ops->init(dev);

3282
	kvm_get_kvm(kvm);
3283
	ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
S
Scott Wood 已提交
3284
	if (ret < 0) {
3285
		kvm_put_kvm_no_destroy(kvm);
3286 3287 3288
		mutex_lock(&kvm->lock);
		list_del(&dev->vm_node);
		mutex_unlock(&kvm->lock);
3289
		ops->destroy(dev);
S
Scott Wood 已提交
3290 3291 3292 3293 3294 3295 3296
		return ret;
	}

	cd->fd = ret;
	return 0;
}

3297 3298 3299 3300 3301 3302 3303 3304 3305 3306
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
3307
#ifdef CONFIG_HAVE_KVM_IRQFD
3308
	case KVM_CAP_IRQFD:
3309 3310
	case KVM_CAP_IRQFD_RESAMPLE:
#endif
3311
	case KVM_CAP_IOEVENTFD_ANY_LENGTH:
3312
	case KVM_CAP_CHECK_EXTENSION_VM:
3313
	case KVM_CAP_ENABLE_CAP_VM:
3314
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3315
	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2:
3316
#endif
3317
		return 1;
3318
#ifdef CONFIG_KVM_MMIO
3319 3320
	case KVM_CAP_COALESCED_MMIO:
		return KVM_COALESCED_MMIO_PAGE_OFFSET;
P
Peng Hao 已提交
3321 3322
	case KVM_CAP_COALESCED_PIO:
		return 1;
3323
#endif
3324 3325 3326
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
	case KVM_CAP_IRQ_ROUTING:
		return KVM_MAX_IRQ_ROUTES;
3327 3328 3329 3330
#endif
#if KVM_ADDRESS_SPACE_NUM > 1
	case KVM_CAP_MULTI_ADDRESS_SPACE:
		return KVM_ADDRESS_SPACE_NUM;
3331
#endif
3332 3333
	case KVM_CAP_NR_MEMSLOTS:
		return KVM_USER_MEM_SLOTS;
3334 3335 3336 3337 3338 3339
	default:
		break;
	}
	return kvm_vm_ioctl_check_extension(kvm, arg);
}

3340 3341 3342 3343 3344 3345 3346 3347 3348 3349
int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
						  struct kvm_enable_cap *cap)
{
	return -EINVAL;
}

static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
					   struct kvm_enable_cap *cap)
{
	switch (cap->cap) {
3350
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
3351
	case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2:
3352 3353 3354 3355 3356
		if (cap->flags || (cap->args[0] & ~1))
			return -EINVAL;
		kvm->manual_dirty_log_protect = cap->args[0];
		return 0;
#endif
3357 3358 3359 3360 3361
	default:
		return kvm_vm_ioctl_enable_cap(kvm, cap);
	}
}

A
Avi Kivity 已提交
3362 3363 3364 3365 3366
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;
3367
	int r;
A
Avi Kivity 已提交
3368

3369 3370
	if (kvm->mm != current->mm)
		return -EIO;
A
Avi Kivity 已提交
3371 3372 3373 3374
	switch (ioctl) {
	case KVM_CREATE_VCPU:
		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
		break;
3375 3376 3377 3378 3379 3380 3381 3382 3383
	case KVM_ENABLE_CAP: {
		struct kvm_enable_cap cap;

		r = -EFAULT;
		if (copy_from_user(&cap, argp, sizeof(cap)))
			goto out;
		r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
		break;
	}
3384 3385 3386 3387 3388
	case KVM_SET_USER_MEMORY_REGION: {
		struct kvm_userspace_memory_region kvm_userspace_mem;

		r = -EFAULT;
		if (copy_from_user(&kvm_userspace_mem, argp,
3389
						sizeof(kvm_userspace_mem)))
3390 3391
			goto out;

3392
		r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
A
Avi Kivity 已提交
3393 3394 3395 3396 3397 3398
		break;
	}
	case KVM_GET_DIRTY_LOG: {
		struct kvm_dirty_log log;

		r = -EFAULT;
3399
		if (copy_from_user(&log, argp, sizeof(log)))
A
Avi Kivity 已提交
3400
			goto out;
3401
		r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
A
Avi Kivity 已提交
3402 3403
		break;
	}
3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
	case KVM_CLEAR_DIRTY_LOG: {
		struct kvm_clear_dirty_log log;

		r = -EFAULT;
		if (copy_from_user(&log, argp, sizeof(log)))
			goto out;
		r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
		break;
	}
#endif
3415
#ifdef CONFIG_KVM_MMIO
3416 3417
	case KVM_REGISTER_COALESCED_MMIO: {
		struct kvm_coalesced_mmio_zone zone;
3418

3419
		r = -EFAULT;
3420
		if (copy_from_user(&zone, argp, sizeof(zone)))
3421 3422 3423 3424 3425 3426
			goto out;
		r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
		break;
	}
	case KVM_UNREGISTER_COALESCED_MMIO: {
		struct kvm_coalesced_mmio_zone zone;
3427

3428
		r = -EFAULT;
3429
		if (copy_from_user(&zone, argp, sizeof(zone)))
3430 3431 3432 3433 3434
			goto out;
		r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
		break;
	}
#endif
G
Gregory Haskins 已提交
3435 3436 3437 3438
	case KVM_IRQFD: {
		struct kvm_irqfd data;

		r = -EFAULT;
3439
		if (copy_from_user(&data, argp, sizeof(data)))
G
Gregory Haskins 已提交
3440
			goto out;
3441
		r = kvm_irqfd(kvm, &data);
G
Gregory Haskins 已提交
3442 3443
		break;
	}
G
Gregory Haskins 已提交
3444 3445 3446 3447
	case KVM_IOEVENTFD: {
		struct kvm_ioeventfd data;

		r = -EFAULT;
3448
		if (copy_from_user(&data, argp, sizeof(data)))
G
Gregory Haskins 已提交
3449 3450 3451 3452
			goto out;
		r = kvm_ioeventfd(kvm, &data);
		break;
	}
3453 3454 3455 3456 3457
#ifdef CONFIG_HAVE_KVM_MSI
	case KVM_SIGNAL_MSI: {
		struct kvm_msi msi;

		r = -EFAULT;
3458
		if (copy_from_user(&msi, argp, sizeof(msi)))
3459 3460 3461 3462
			goto out;
		r = kvm_send_userspace_msi(kvm, &msi);
		break;
	}
3463 3464 3465 3466 3467 3468 3469
#endif
#ifdef __KVM_HAVE_IRQ_LINE
	case KVM_IRQ_LINE_STATUS:
	case KVM_IRQ_LINE: {
		struct kvm_irq_level irq_event;

		r = -EFAULT;
3470
		if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
3471 3472
			goto out;

3473 3474
		r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
					ioctl == KVM_IRQ_LINE_STATUS);
3475 3476 3477 3478 3479
		if (r)
			goto out;

		r = -EFAULT;
		if (ioctl == KVM_IRQ_LINE_STATUS) {
3480
			if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
3481 3482 3483 3484 3485 3486
				goto out;
		}

		r = 0;
		break;
	}
3487
#endif
3488 3489 3490 3491
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
	case KVM_SET_GSI_ROUTING: {
		struct kvm_irq_routing routing;
		struct kvm_irq_routing __user *urouting;
3492
		struct kvm_irq_routing_entry *entries = NULL;
3493 3494 3495 3496 3497

		r = -EFAULT;
		if (copy_from_user(&routing, argp, sizeof(routing)))
			goto out;
		r = -EINVAL;
3498 3499
		if (!kvm_arch_can_set_irq_routing(kvm))
			goto out;
3500
		if (routing.nr > KVM_MAX_IRQ_ROUTES)
3501 3502 3503
			goto out;
		if (routing.flags)
			goto out;
3504 3505
		if (routing.nr) {
			r = -ENOMEM;
3506 3507
			entries = vmalloc(array_size(sizeof(*entries),
						     routing.nr));
3508 3509 3510 3511 3512 3513 3514 3515
			if (!entries)
				goto out;
			r = -EFAULT;
			urouting = argp;
			if (copy_from_user(entries, urouting->entries,
					   routing.nr * sizeof(*entries)))
				goto out_free_irq_routing;
		}
3516 3517
		r = kvm_set_irq_routing(kvm, entries, routing.nr,
					routing.flags);
3518
out_free_irq_routing:
3519 3520 3521 3522
		vfree(entries);
		break;
	}
#endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
S
Scott Wood 已提交
3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540
	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;
	}
3541 3542 3543
	case KVM_CHECK_EXTENSION:
		r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
		break;
3544
	default:
3545
		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
3546 3547 3548 3549 3550
	}
out:
	return r;
}

3551
#ifdef CONFIG_KVM_COMPAT
3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575
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;

		if (copy_from_user(&compat_log, (void __user *)arg,
				   sizeof(compat_log)))
3576
			return -EFAULT;
3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591
		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);
	}
	return r;
}
#endif

3592
static struct file_operations kvm_vm_fops = {
3593 3594
	.release        = kvm_vm_release,
	.unlocked_ioctl = kvm_vm_ioctl,
3595
	.llseek		= noop_llseek,
3596
	KVM_COMPAT(kvm_vm_compat_ioctl),
3597 3598
};

3599
static int kvm_dev_ioctl_create_vm(unsigned long type)
3600
{
3601
	int r;
3602
	struct kvm *kvm;
3603
	struct file *file;
3604

3605
	kvm = kvm_create_vm(type);
3606 3607
	if (IS_ERR(kvm))
		return PTR_ERR(kvm);
3608
#ifdef CONFIG_KVM_MMIO
3609
	r = kvm_coalesced_mmio_init(kvm);
3610 3611
	if (r < 0)
		goto put_kvm;
3612
#endif
3613
	r = get_unused_fd_flags(O_CLOEXEC);
3614 3615 3616
	if (r < 0)
		goto put_kvm;

3617 3618 3619
	file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
	if (IS_ERR(file)) {
		put_unused_fd(r);
3620 3621
		r = PTR_ERR(file);
		goto put_kvm;
3622
	}
3623

3624 3625 3626 3627 3628 3629
	/*
	 * Don't call kvm_put_kvm anymore at this point; file->f_op is
	 * already set, with ->release() being kvm_vm_release().  In error
	 * cases it will be called by the final fput(file) and will take
	 * care of doing kvm_put_kvm(kvm).
	 */
3630
	if (kvm_create_vm_debugfs(kvm, r) < 0) {
3631 3632
		put_unused_fd(r);
		fput(file);
3633 3634
		return -ENOMEM;
	}
3635
	kvm_uevent_notify_change(KVM_EVENT_CREATE_VM, kvm);
3636

3637
	fd_install(r, file);
3638
	return r;
3639 3640 3641 3642

put_kvm:
	kvm_put_kvm(kvm);
	return r;
3643 3644 3645 3646 3647
}

static long kvm_dev_ioctl(struct file *filp,
			  unsigned int ioctl, unsigned long arg)
{
3648
	long r = -EINVAL;
3649 3650 3651

	switch (ioctl) {
	case KVM_GET_API_VERSION:
3652 3653
		if (arg)
			goto out;
3654 3655 3656
		r = KVM_API_VERSION;
		break;
	case KVM_CREATE_VM:
3657
		r = kvm_dev_ioctl_create_vm(arg);
3658
		break;
3659
	case KVM_CHECK_EXTENSION:
3660
		r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
3661
		break;
3662 3663 3664
	case KVM_GET_VCPU_MMAP_SIZE:
		if (arg)
			goto out;
3665 3666 3667
		r = PAGE_SIZE;     /* struct kvm_run */
#ifdef CONFIG_X86
		r += PAGE_SIZE;    /* pio data page */
3668
#endif
3669
#ifdef CONFIG_KVM_MMIO
3670
		r += PAGE_SIZE;    /* coalesced mmio ring page */
3671
#endif
3672
		break;
3673 3674 3675
	case KVM_TRACE_ENABLE:
	case KVM_TRACE_PAUSE:
	case KVM_TRACE_DISABLE:
3676
		r = -EOPNOTSUPP;
3677
		break;
A
Avi Kivity 已提交
3678
	default:
3679
		return kvm_arch_dev_ioctl(filp, ioctl, arg);
A
Avi Kivity 已提交
3680 3681 3682 3683 3684 3685 3686
	}
out:
	return r;
}

static struct file_operations kvm_chardev_ops = {
	.unlocked_ioctl = kvm_dev_ioctl,
3687
	.llseek		= noop_llseek,
3688
	KVM_COMPAT(kvm_dev_ioctl),
A
Avi Kivity 已提交
3689 3690 3691
};

static struct miscdevice kvm_dev = {
A
Avi Kivity 已提交
3692
	KVM_MINOR,
A
Avi Kivity 已提交
3693 3694 3695 3696
	"kvm",
	&kvm_chardev_ops,
};

3697
static void hardware_enable_nolock(void *junk)
3698 3699
{
	int cpu = raw_smp_processor_id();
3700
	int r;
3701

3702
	if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
3703
		return;
3704

3705
	cpumask_set_cpu(cpu, cpus_hardware_enabled);
3706

3707
	r = kvm_arch_hardware_enable();
3708 3709 3710 3711

	if (r) {
		cpumask_clear_cpu(cpu, cpus_hardware_enabled);
		atomic_inc(&hardware_enable_failed);
X
Xiubo Li 已提交
3712
		pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
3713
	}
3714 3715
}

3716
static int kvm_starting_cpu(unsigned int cpu)
3717
{
3718
	raw_spin_lock(&kvm_count_lock);
3719 3720
	if (kvm_usage_count)
		hardware_enable_nolock(NULL);
3721
	raw_spin_unlock(&kvm_count_lock);
3722
	return 0;
3723 3724 3725
}

static void hardware_disable_nolock(void *junk)
3726 3727 3728
{
	int cpu = raw_smp_processor_id();

3729
	if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
3730
		return;
3731
	cpumask_clear_cpu(cpu, cpus_hardware_enabled);
3732
	kvm_arch_hardware_disable();
3733 3734
}

3735
static int kvm_dying_cpu(unsigned int cpu)
3736
{
3737
	raw_spin_lock(&kvm_count_lock);
3738 3739
	if (kvm_usage_count)
		hardware_disable_nolock(NULL);
3740
	raw_spin_unlock(&kvm_count_lock);
3741
	return 0;
3742 3743
}

3744 3745 3746 3747 3748 3749
static void hardware_disable_all_nolock(void)
{
	BUG_ON(!kvm_usage_count);

	kvm_usage_count--;
	if (!kvm_usage_count)
3750
		on_each_cpu(hardware_disable_nolock, NULL, 1);
3751 3752 3753 3754
}

static void hardware_disable_all(void)
{
3755
	raw_spin_lock(&kvm_count_lock);
3756
	hardware_disable_all_nolock();
3757
	raw_spin_unlock(&kvm_count_lock);
3758 3759 3760 3761 3762 3763
}

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

3764
	raw_spin_lock(&kvm_count_lock);
3765 3766 3767 3768

	kvm_usage_count++;
	if (kvm_usage_count == 1) {
		atomic_set(&hardware_enable_failed, 0);
3769
		on_each_cpu(hardware_enable_nolock, NULL, 1);
3770 3771 3772 3773 3774 3775 3776

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

3777
	raw_spin_unlock(&kvm_count_lock);
3778 3779 3780 3781

	return r;
}

3782
static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
M
Mike Day 已提交
3783
		      void *v)
3784
{
3785 3786 3787 3788 3789 3790
	/*
	 * 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
3791
	pr_info("kvm: exiting hardware virtualization\n");
3792
	kvm_rebooting = true;
3793
	on_each_cpu(hardware_disable_nolock, NULL, 1);
3794 3795 3796 3797 3798 3799 3800 3801
	return NOTIFY_OK;
}

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

M
Marcelo Tosatti 已提交
3802
static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
3803 3804 3805 3806
{
	int i;

	for (i = 0; i < bus->dev_count; i++) {
3807
		struct kvm_io_device *pos = bus->range[i].dev;
3808 3809 3810

		kvm_iodevice_destructor(pos);
	}
M
Marcelo Tosatti 已提交
3811
	kfree(bus);
3812 3813
}

3814
static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
X
Xiubo Li 已提交
3815
				 const struct kvm_io_range *r2)
3816
{
J
Jason Wang 已提交
3817 3818 3819 3820
	gpa_t addr1 = r1->addr;
	gpa_t addr2 = r2->addr;

	if (addr1 < addr2)
3821
		return -1;
J
Jason Wang 已提交
3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832 3833

	/* 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)
3834
		return 1;
J
Jason Wang 已提交
3835

3836 3837 3838
	return 0;
}

3839 3840
static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
{
3841
	return kvm_io_bus_cmp(p1, p2);
3842 3843
}

G
Geoff Levand 已提交
3844
static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861
			     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;

3862
	while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
3863 3864 3865 3866 3867
		off--;

	return off;
}

3868
static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
C
Cornelia Huck 已提交
3869 3870 3871 3872 3873 3874 3875 3876 3877
			      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 &&
3878
		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3879
		if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
C
Cornelia Huck 已提交
3880 3881 3882 3883 3884 3885 3886 3887
					range->len, val))
			return idx;
		idx++;
	}

	return -EOPNOTSUPP;
}

3888
/* kvm_io_bus_write - called under kvm->slots_lock */
3889
int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
3890
		     int len, const void *val)
3891
{
3892
	struct kvm_io_bus *bus;
3893
	struct kvm_io_range range;
C
Cornelia Huck 已提交
3894
	int r;
3895 3896 3897 3898 3899

	range = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};
3900

3901
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3902 3903
	if (!bus)
		return -ENOMEM;
3904
	r = __kvm_io_bus_write(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3905 3906
	return r < 0 ? r : 0;
}
L
Leo Yan 已提交
3907
EXPORT_SYMBOL_GPL(kvm_io_bus_write);
C
Cornelia Huck 已提交
3908 3909

/* kvm_io_bus_write_cookie - called under kvm->slots_lock */
3910 3911
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
3912 3913 3914 3915 3916 3917 3918 3919 3920
{
	struct kvm_io_bus *bus;
	struct kvm_io_range range;

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

3921
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3922 3923
	if (!bus)
		return -ENOMEM;
C
Cornelia Huck 已提交
3924 3925 3926

	/* First try the device referenced by cookie. */
	if ((cookie >= 0) && (cookie < bus->dev_count) &&
3927
	    (kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
3928
		if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
C
Cornelia Huck 已提交
3929 3930 3931 3932 3933 3934 3935
					val))
			return cookie;

	/*
	 * cookie contained garbage; fall back to search and return the
	 * correct cookie value.
	 */
3936
	return __kvm_io_bus_write(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3937 3938
}

3939 3940
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
3941 3942 3943 3944
{
	int idx;

	idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
3945 3946 3947 3948
	if (idx < 0)
		return -EOPNOTSUPP;

	while (idx < bus->dev_count &&
3949
		kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
3950
		if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
C
Cornelia Huck 已提交
3951 3952
				       range->len, val))
			return idx;
3953 3954 3955
		idx++;
	}

3956 3957
	return -EOPNOTSUPP;
}
3958

3959
/* kvm_io_bus_read - called under kvm->slots_lock */
3960
int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
M
Marcelo Tosatti 已提交
3961
		    int len, void *val)
3962
{
3963
	struct kvm_io_bus *bus;
3964
	struct kvm_io_range range;
C
Cornelia Huck 已提交
3965
	int r;
3966 3967 3968 3969 3970

	range = (struct kvm_io_range) {
		.addr = addr,
		.len = len,
	};
M
Marcelo Tosatti 已提交
3971

3972
	bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
3973 3974
	if (!bus)
		return -ENOMEM;
3975
	r = __kvm_io_bus_read(vcpu, bus, &range, val);
C
Cornelia Huck 已提交
3976 3977
	return r < 0 ? r : 0;
}
3978

3979
/* Caller must hold slots_lock. */
3980 3981
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
			    int len, struct kvm_io_device *dev)
3982
{
3983
	int i;
M
Marcelo Tosatti 已提交
3984
	struct kvm_io_bus *new_bus, *bus;
3985
	struct kvm_io_range range;
3986

3987
	bus = kvm_get_bus(kvm, bus_idx);
3988 3989 3990
	if (!bus)
		return -ENOMEM;

3991 3992
	/* exclude ioeventfd which is limited by maximum fd */
	if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
3993
		return -ENOSPC;
3994

3995
	new_bus = kmalloc(struct_size(bus, range, bus->dev_count + 1),
3996
			  GFP_KERNEL_ACCOUNT);
M
Marcelo Tosatti 已提交
3997 3998
	if (!new_bus)
		return -ENOMEM;
3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014

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

	for (i = 0; i < bus->dev_count; i++)
		if (kvm_io_bus_cmp(&bus->range[i], &range) > 0)
			break;

	memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
	new_bus->dev_count++;
	new_bus->range[i] = range;
	memcpy(new_bus->range + i + 1, bus->range + i,
		(bus->dev_count - i) * sizeof(struct kvm_io_range));
M
Marcelo Tosatti 已提交
4015 4016 4017
	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
	synchronize_srcu_expedited(&kvm->srcu);
	kfree(bus);
4018 4019 4020 4021

	return 0;
}

4022
/* Caller must hold slots_lock. */
4023 4024
void kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
			       struct kvm_io_device *dev)
4025
{
4026
	int i;
M
Marcelo Tosatti 已提交
4027
	struct kvm_io_bus *new_bus, *bus;
4028

4029
	bus = kvm_get_bus(kvm, bus_idx);
4030
	if (!bus)
4031
		return;
4032

4033 4034
	for (i = 0; i < bus->dev_count; i++)
		if (bus->range[i].dev == dev) {
4035 4036
			break;
		}
M
Marcelo Tosatti 已提交
4037

4038 4039
	if (i == bus->dev_count)
		return;
4040

4041
	new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1),
4042
			  GFP_KERNEL_ACCOUNT);
4043 4044 4045 4046
	if (!new_bus)  {
		pr_err("kvm: failed to shrink bus, removing it completely\n");
		goto broken;
	}
4047 4048 4049 4050 4051

	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
4052

4053
broken:
M
Marcelo Tosatti 已提交
4054 4055 4056
	rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
	synchronize_srcu_expedited(&kvm->srcu);
	kfree(bus);
4057
	return;
4058 4059
}

4060 4061 4062 4063 4064 4065 4066 4067 4068 4069
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);
4070 4071
	if (!bus)
		goto out_unlock;
4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085

	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);

4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097
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.
	 */
4098
	if (!refcount_inc_not_zero(&stat_data->kvm->users_count))
4099 4100
		return -ENOENT;

4101
	if (simple_attr_open(inode, file, get,
4102 4103 4104
		    KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & 0222
		    ? set : NULL,
		    fmt)) {
4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122
		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;
}

4123
static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
4124
{
4125
	*val = *(ulong *)((void *)kvm + offset);
4126

4127 4128 4129 4130 4131 4132
	return 0;
}

static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
{
	*(ulong *)((void *)kvm + offset) = 0;
4133 4134 4135 4136

	return 0;
}

4137
static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
4138
{
4139 4140
	int i;
	struct kvm_vcpu *vcpu;
4141

4142
	*val = 0;
4143

4144 4145
	kvm_for_each_vcpu(i, vcpu, kvm)
		*val += *(u64 *)((void *)vcpu + offset);
4146 4147 4148 4149

	return 0;
}

4150
static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
4151
{
4152 4153
	int i;
	struct kvm_vcpu *vcpu;
4154

4155 4156 4157 4158 4159
	kvm_for_each_vcpu(i, vcpu, kvm)
		*(u64 *)((void *)vcpu + offset) = 0;

	return 0;
}
4160

4161
static int kvm_stat_data_get(void *data, u64 *val)
4162
{
4163
	int r = -EFAULT;
4164 4165
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;

4166 4167 4168 4169 4170 4171 4172 4173 4174 4175
	switch (stat_data->dbgfs_item->kind) {
	case KVM_STAT_VM:
		r = kvm_get_stat_per_vm(stat_data->kvm,
					stat_data->dbgfs_item->offset, val);
		break;
	case KVM_STAT_VCPU:
		r = kvm_get_stat_per_vcpu(stat_data->kvm,
					  stat_data->dbgfs_item->offset, val);
		break;
	}
4176

4177
	return r;
4178 4179
}

4180
static int kvm_stat_data_clear(void *data, u64 val)
4181
{
4182
	int r = -EFAULT;
4183 4184 4185 4186 4187
	struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;

	if (val)
		return -EINVAL;

4188 4189 4190 4191 4192 4193 4194 4195 4196 4197
	switch (stat_data->dbgfs_item->kind) {
	case KVM_STAT_VM:
		r = kvm_clear_stat_per_vm(stat_data->kvm,
					  stat_data->dbgfs_item->offset);
		break;
	case KVM_STAT_VCPU:
		r = kvm_clear_stat_per_vcpu(stat_data->kvm,
					    stat_data->dbgfs_item->offset);
		break;
	}
4198

4199
	return r;
4200 4201
}

4202
static int kvm_stat_data_open(struct inode *inode, struct file *file)
4203 4204
{
	__simple_attr_check_format("%llu\n", 0ull);
4205 4206
	return kvm_debugfs_open(inode, file, kvm_stat_data_get,
				kvm_stat_data_clear, "%llu\n");
4207 4208
}

4209 4210 4211
static const struct file_operations stat_fops_per_vm = {
	.owner = THIS_MODULE,
	.open = kvm_stat_data_open,
4212
	.release = kvm_debugfs_release,
4213 4214 4215
	.read = simple_attr_read,
	.write = simple_attr_write,
	.llseek = no_llseek,
4216 4217
};

4218
static int vm_stat_get(void *_offset, u64 *val)
4219 4220 4221
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
4222
	u64 tmp_val;
4223

4224
	*val = 0;
J
Junaid Shahid 已提交
4225
	mutex_lock(&kvm_lock);
4226
	list_for_each_entry(kvm, &vm_list, vm_list) {
4227
		kvm_get_stat_per_vm(kvm, offset, &tmp_val);
4228 4229
		*val += tmp_val;
	}
J
Junaid Shahid 已提交
4230
	mutex_unlock(&kvm_lock);
4231
	return 0;
4232 4233
}

4234 4235 4236 4237 4238 4239 4240 4241
static int vm_stat_clear(void *_offset, u64 val)
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;

	if (val)
		return -EINVAL;

J
Junaid Shahid 已提交
4242
	mutex_lock(&kvm_lock);
4243
	list_for_each_entry(kvm, &vm_list, vm_list) {
4244
		kvm_clear_stat_per_vm(kvm, offset);
4245
	}
J
Junaid Shahid 已提交
4246
	mutex_unlock(&kvm_lock);
4247 4248 4249 4250 4251

	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, vm_stat_clear, "%llu\n");
4252

4253
static int vcpu_stat_get(void *_offset, u64 *val)
A
Avi Kivity 已提交
4254 4255 4256
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;
4257
	u64 tmp_val;
A
Avi Kivity 已提交
4258

4259
	*val = 0;
J
Junaid Shahid 已提交
4260
	mutex_lock(&kvm_lock);
4261
	list_for_each_entry(kvm, &vm_list, vm_list) {
4262
		kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
4263 4264
		*val += tmp_val;
	}
J
Junaid Shahid 已提交
4265
	mutex_unlock(&kvm_lock);
4266
	return 0;
A
Avi Kivity 已提交
4267 4268
}

4269 4270 4271 4272 4273 4274 4275 4276
static int vcpu_stat_clear(void *_offset, u64 val)
{
	unsigned offset = (long)_offset;
	struct kvm *kvm;

	if (val)
		return -EINVAL;

J
Junaid Shahid 已提交
4277
	mutex_lock(&kvm_lock);
4278
	list_for_each_entry(kvm, &vm_list, vm_list) {
4279
		kvm_clear_stat_per_vcpu(kvm, offset);
4280
	}
J
Junaid Shahid 已提交
4281
	mutex_unlock(&kvm_lock);
4282 4283 4284 4285 4286 4287

	return 0;
}

DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, vcpu_stat_clear,
			"%llu\n");
4288

4289
static const struct file_operations *stat_fops[] = {
4290 4291 4292
	[KVM_STAT_VCPU] = &vcpu_stat_fops,
	[KVM_STAT_VM]   = &vm_stat_fops,
};
A
Avi Kivity 已提交
4293

4294 4295 4296 4297 4298 4299 4300 4301
static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
{
	struct kobj_uevent_env *env;
	unsigned long long created, active;

	if (!kvm_dev.this_device || !kvm)
		return;

J
Junaid Shahid 已提交
4302
	mutex_lock(&kvm_lock);
4303 4304 4305 4306 4307 4308 4309 4310
	if (type == KVM_EVENT_CREATE_VM) {
		kvm_createvm_count++;
		kvm_active_vms++;
	} else if (type == KVM_EVENT_DESTROY_VM) {
		kvm_active_vms--;
	}
	created = kvm_createvm_count;
	active = kvm_active_vms;
J
Junaid Shahid 已提交
4311
	mutex_unlock(&kvm_lock);
4312

4313
	env = kzalloc(sizeof(*env), GFP_KERNEL_ACCOUNT);
4314 4315 4316 4317 4318 4319
	if (!env)
		return;

	add_uevent_var(env, "CREATED=%llu", created);
	add_uevent_var(env, "COUNT=%llu", active);

4320
	if (type == KVM_EVENT_CREATE_VM) {
4321
		add_uevent_var(env, "EVENT=create");
4322 4323
		kvm->userspace_pid = task_pid_nr(current);
	} else if (type == KVM_EVENT_DESTROY_VM) {
4324
		add_uevent_var(env, "EVENT=destroy");
4325 4326
	}
	add_uevent_var(env, "PID=%d", kvm->userspace_pid);
4327

4328
	if (!IS_ERR_OR_NULL(kvm->debugfs_dentry)) {
4329
		char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL_ACCOUNT);
4330 4331 4332 4333 4334 4335

		if (p) {
			tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX);
			if (!IS_ERR(tmp))
				add_uevent_var(env, "STATS_PATH=%s", tmp);
			kfree(p);
4336 4337 4338 4339 4340 4341 4342 4343
		}
	}
	/* no need for checks, since we are adding at most only 5 keys */
	env->envp[env->envp_idx++] = NULL;
	kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp);
	kfree(env);
}

4344
static void kvm_init_debug(void)
A
Avi Kivity 已提交
4345 4346 4347
{
	struct kvm_stats_debugfs_item *p;

4348
	kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
4349

4350 4351
	kvm_debugfs_num_entries = 0;
	for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
4352 4353
		debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
				    kvm_debugfs_dir, (void *)(long)p->offset,
4354
				    stat_fops[p->kind]);
4355
	}
A
Avi Kivity 已提交
4356 4357
}

4358
static int kvm_suspend(void)
4359
{
4360
	if (kvm_usage_count)
4361
		hardware_disable_nolock(NULL);
4362 4363 4364
	return 0;
}

4365
static void kvm_resume(void)
4366
{
4367
	if (kvm_usage_count) {
4368 4369 4370
#ifdef CONFIG_LOCKDEP
		WARN_ON(lockdep_is_held(&kvm_count_lock));
#endif
4371
		hardware_enable_nolock(NULL);
4372
	}
4373 4374
}

4375
static struct syscore_ops kvm_syscore_ops = {
4376 4377 4378 4379
	.suspend = kvm_suspend,
	.resume = kvm_resume,
};

4380 4381 4382 4383 4384 4385 4386 4387 4388
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);
4389

4390
	WRITE_ONCE(vcpu->preempted, false);
4391
	WRITE_ONCE(vcpu->ready, false);
4392

4393
	__this_cpu_write(kvm_running_vcpu, vcpu);
R
Radim Krčmář 已提交
4394
	kvm_arch_sched_in(vcpu, cpu);
4395
	kvm_arch_vcpu_load(vcpu, cpu);
4396 4397 4398 4399 4400 4401 4402
}

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

4403
	if (current->state == TASK_RUNNING) {
4404
		WRITE_ONCE(vcpu->preempted, true);
4405 4406
		WRITE_ONCE(vcpu->ready, true);
	}
4407
	kvm_arch_vcpu_put(vcpu);
4408 4409 4410 4411 4412
	__this_cpu_write(kvm_running_vcpu, NULL);
}

/**
 * kvm_get_running_vcpu - get the vcpu running on the current CPU.
4413 4414 4415 4416 4417 4418
 *
 * We can disable preemption locally around accessing the per-CPU variable,
 * and use the resolved vcpu pointer after enabling preemption again,
 * because even if the current thread is migrated to another CPU, reading
 * the per-CPU value later will give us the same value as we update the
 * per-CPU variable in the preempt notifier handlers.
4419 4420 4421
 */
struct kvm_vcpu *kvm_get_running_vcpu(void)
{
4422 4423 4424 4425 4426 4427 4428
	struct kvm_vcpu *vcpu;

	preempt_disable();
	vcpu = __this_cpu_read(kvm_running_vcpu);
	preempt_enable();

	return vcpu;
4429 4430 4431 4432 4433 4434 4435 4436
}

/**
 * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
 */
struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
{
        return &kvm_running_vcpu;
4437 4438
}

4439 4440 4441 4442 4443
static void check_processor_compat(void *rtn)
{
	*(int *)rtn = kvm_arch_check_processor_compat();
}

4444
int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
4445
		  struct module *module)
A
Avi Kivity 已提交
4446 4447
{
	int r;
Y
Yang, Sheng 已提交
4448
	int cpu;
A
Avi Kivity 已提交
4449

4450 4451
	r = kvm_arch_init(opaque);
	if (r)
4452
		goto out_fail;
4453

4454 4455 4456 4457
	/*
	 * 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
4458 4459
	 * kvm_arch_init must be called before kvm_irqfd_init to avoid creating
	 * conflicts in case kvm is already setup for another implementation.
4460
	 */
P
Paolo Bonzini 已提交
4461 4462 4463
	r = kvm_irqfd_init();
	if (r)
		goto out_irqfd;
4464

4465
	if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
4466 4467 4468 4469
		r = -ENOMEM;
		goto out_free_0;
	}

4470
	r = kvm_arch_hardware_setup();
A
Avi Kivity 已提交
4471
	if (r < 0)
4472
		goto out_free_1;
A
Avi Kivity 已提交
4473

Y
Yang, Sheng 已提交
4474
	for_each_online_cpu(cpu) {
4475
		smp_call_function_single(cpu, check_processor_compat, &r, 1);
Y
Yang, Sheng 已提交
4476
		if (r < 0)
4477
			goto out_free_2;
Y
Yang, Sheng 已提交
4478 4479
	}

T
Thomas Gleixner 已提交
4480
	r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "kvm/cpu:starting",
4481
				      kvm_starting_cpu, kvm_dying_cpu);
A
Avi Kivity 已提交
4482
	if (r)
4483
		goto out_free_2;
A
Avi Kivity 已提交
4484 4485
	register_reboot_notifier(&kvm_reboot_notifier);

4486
	/* A kmem cache lets us meet the alignment requirements of fx_save. */
4487 4488
	if (!vcpu_align)
		vcpu_align = __alignof__(struct kvm_vcpu);
4489 4490 4491 4492 4493 4494
	kvm_vcpu_cache =
		kmem_cache_create_usercopy("kvm_vcpu", vcpu_size, vcpu_align,
					   SLAB_ACCOUNT,
					   offsetof(struct kvm_vcpu, arch),
					   sizeof_field(struct kvm_vcpu, arch),
					   NULL);
4495 4496
	if (!kvm_vcpu_cache) {
		r = -ENOMEM;
4497
		goto out_free_3;
4498 4499
	}

4500 4501 4502 4503
	r = kvm_async_pf_init();
	if (r)
		goto out_free;

A
Avi Kivity 已提交
4504
	kvm_chardev_ops.owner = module;
4505 4506
	kvm_vm_fops.owner = module;
	kvm_vcpu_fops.owner = module;
A
Avi Kivity 已提交
4507 4508 4509

	r = misc_register(&kvm_dev);
	if (r) {
X
Xiubo Li 已提交
4510
		pr_err("kvm: misc device register failed\n");
4511
		goto out_unreg;
A
Avi Kivity 已提交
4512 4513
	}

4514 4515
	register_syscore_ops(&kvm_syscore_ops);

4516 4517 4518
	kvm_preempt_ops.sched_in = kvm_sched_in;
	kvm_preempt_ops.sched_out = kvm_sched_out;

4519
	kvm_init_debug();
4520

P
Paolo Bonzini 已提交
4521 4522 4523
	r = kvm_vfio_ops_init();
	WARN_ON(r);

4524
	return 0;
A
Avi Kivity 已提交
4525

4526 4527
out_unreg:
	kvm_async_pf_deinit();
A
Avi Kivity 已提交
4528
out_free:
4529
	kmem_cache_destroy(kvm_vcpu_cache);
4530
out_free_3:
A
Avi Kivity 已提交
4531
	unregister_reboot_notifier(&kvm_reboot_notifier);
4532
	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
4533
out_free_2:
4534
	kvm_arch_hardware_unsetup();
4535
out_free_1:
4536
	free_cpumask_var(cpus_hardware_enabled);
4537
out_free_0:
4538
	kvm_irqfd_exit();
P
Paolo Bonzini 已提交
4539
out_irqfd:
4540 4541
	kvm_arch_exit();
out_fail:
A
Avi Kivity 已提交
4542 4543
	return r;
}
4544
EXPORT_SYMBOL_GPL(kvm_init);
A
Avi Kivity 已提交
4545

4546
void kvm_exit(void)
A
Avi Kivity 已提交
4547
{
4548
	debugfs_remove_recursive(kvm_debugfs_dir);
A
Avi Kivity 已提交
4549
	misc_deregister(&kvm_dev);
4550
	kmem_cache_destroy(kvm_vcpu_cache);
4551
	kvm_async_pf_deinit();
4552
	unregister_syscore_ops(&kvm_syscore_ops);
A
Avi Kivity 已提交
4553
	unregister_reboot_notifier(&kvm_reboot_notifier);
4554
	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
4555
	on_each_cpu(hardware_disable_nolock, NULL, 1);
4556
	kvm_arch_hardware_unsetup();
4557
	kvm_arch_exit();
4558
	kvm_irqfd_exit();
4559
	free_cpumask_var(cpus_hardware_enabled);
4560
	kvm_vfio_ops_exit();
A
Avi Kivity 已提交
4561
}
4562
EXPORT_SYMBOL_GPL(kvm_exit);
4563 4564 4565 4566 4567 4568 4569 4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645

struct kvm_vm_worker_thread_context {
	struct kvm *kvm;
	struct task_struct *parent;
	struct completion init_done;
	kvm_vm_thread_fn_t thread_fn;
	uintptr_t data;
	int err;
};

static int kvm_vm_worker_thread(void *context)
{
	/*
	 * The init_context is allocated on the stack of the parent thread, so
	 * we have to locally copy anything that is needed beyond initialization
	 */
	struct kvm_vm_worker_thread_context *init_context = context;
	struct kvm *kvm = init_context->kvm;
	kvm_vm_thread_fn_t thread_fn = init_context->thread_fn;
	uintptr_t data = init_context->data;
	int err;

	err = kthread_park(current);
	/* kthread_park(current) is never supposed to return an error */
	WARN_ON(err != 0);
	if (err)
		goto init_complete;

	err = cgroup_attach_task_all(init_context->parent, current);
	if (err) {
		kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
			__func__, err);
		goto init_complete;
	}

	set_user_nice(current, task_nice(init_context->parent));

init_complete:
	init_context->err = err;
	complete(&init_context->init_done);
	init_context = NULL;

	if (err)
		return err;

	/* Wait to be woken up by the spawner before proceeding. */
	kthread_parkme();

	if (!kthread_should_stop())
		err = thread_fn(kvm, data);

	return err;
}

int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
				uintptr_t data, const char *name,
				struct task_struct **thread_ptr)
{
	struct kvm_vm_worker_thread_context init_context = {};
	struct task_struct *thread;

	*thread_ptr = NULL;
	init_context.kvm = kvm;
	init_context.parent = current;
	init_context.thread_fn = thread_fn;
	init_context.data = data;
	init_completion(&init_context.init_done);

	thread = kthread_run(kvm_vm_worker_thread, &init_context,
			     "%s-%d", name, task_pid_nr(current));
	if (IS_ERR(thread))
		return PTR_ERR(thread);

	/* kthread_run is never supposed to return NULL */
	WARN_ON(thread == NULL);

	wait_for_completion(&init_context.init_done);

	if (!init_context.err)
		*thread_ptr = thread;

	return init_context.err;
}