Linux-2.6.33.2/virt/kvm/kvm_main.c
/*
* 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.
*
* Authors:
* Avi Kivity <avi@qumranet.com>
* Yaniv Kamay <yaniv@qumranet.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "iodev.h"
#include <linux/kvm_host.h>
#include <linux/kvm.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/percpu.h>
#include <linux/gfp.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>
#include <linux/sysdev.h>
#include <linux/cpu.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/smp.h>
#include <linux/anon_inodes.h>
#include <linux/profile.h>
#include <linux/kvm_para.h>
#include <linux/pagemap.h>
#include <linux/mman.h>
#include <linux/swap.h>
#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/compat.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm-generic/bitops/le.h>
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
#include "coalesced_mmio.h"
#endif
#define CREATE_TRACE_POINTS
#include <trace/events/kvm.h>
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
/*
* Ordering of locks:
*
* kvm->lock --> kvm->slots_lock --> kvm->irq_lock
*/
DEFINE_SPINLOCK(kvm_lock);
LIST_HEAD(vm_list);
static cpumask_var_t cpus_hardware_enabled;
static int kvm_usage_count = 0;
static atomic_t hardware_enable_failed;
struct kmem_cache *kvm_vcpu_cache;
EXPORT_SYMBOL_GPL(kvm_vcpu_cache);
static __read_mostly struct preempt_ops kvm_preempt_ops;
struct dentry *kvm_debugfs_dir;
static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
unsigned long arg);
static int hardware_enable_all(void);
static void hardware_disable_all(void);
static bool kvm_rebooting;
static bool largepages_enabled = true;
inline int kvm_is_mmio_pfn(pfn_t pfn)
{
if (pfn_valid(pfn)) {
struct page *page = compound_head(pfn_to_page(pfn));
return PageReserved(page);
}
return true;
}
/*
* Switches to specified vcpu, until a matching vcpu_put()
*/
void vcpu_load(struct kvm_vcpu *vcpu)
{
int cpu;
mutex_lock(&vcpu->mutex);
cpu = get_cpu();
preempt_notifier_register(&vcpu->preempt_notifier);
kvm_arch_vcpu_load(vcpu, cpu);
put_cpu();
}
void vcpu_put(struct kvm_vcpu *vcpu)
{
preempt_disable();
kvm_arch_vcpu_put(vcpu);
preempt_notifier_unregister(&vcpu->preempt_notifier);
preempt_enable();
mutex_unlock(&vcpu->mutex);
}
static void ack_flush(void *_completed)
{
}
static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
{
int i, cpu, me;
cpumask_var_t cpus;
bool called = true;
struct kvm_vcpu *vcpu;
zalloc_cpumask_var(&cpus, GFP_ATOMIC);
spin_lock(&kvm->requests_lock);
me = smp_processor_id();
kvm_for_each_vcpu(i, vcpu, kvm) {
if (test_and_set_bit(req, &vcpu->requests))
continue;
cpu = vcpu->cpu;
if (cpus != NULL && cpu != -1 && cpu != me)
cpumask_set_cpu(cpu, cpus);
}
if (unlikely(cpus == NULL))
smp_call_function_many(cpu_online_mask, ack_flush, NULL, 1);
else if (!cpumask_empty(cpus))
smp_call_function_many(cpus, ack_flush, NULL, 1);
else
called = false;
spin_unlock(&kvm->requests_lock);
free_cpumask_var(cpus);
return called;
}
void kvm_flush_remote_tlbs(struct kvm *kvm)
{
if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
++kvm->stat.remote_tlb_flush;
}
void kvm_reload_remote_mmus(struct kvm *kvm)
{
make_all_cpus_request(kvm, KVM_REQ_MMU_RELOAD);
}
int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
{
struct page *page;
int r;
mutex_init(&vcpu->mutex);
vcpu->cpu = -1;
vcpu->kvm = kvm;
vcpu->vcpu_id = id;
init_waitqueue_head(&vcpu->wq);
page = alloc_page(GFP_KERNEL | __GFP_ZERO);
if (!page) {
r = -ENOMEM;
goto fail;
}
vcpu->run = page_address(page);
r = kvm_arch_vcpu_init(vcpu);
if (r < 0)
goto fail_free_run;
return 0;
fail_free_run:
free_page((unsigned long)vcpu->run);
fail:
return r;
}
EXPORT_SYMBOL_GPL(kvm_vcpu_init);
void kvm_vcpu_uninit(struct kvm_vcpu *vcpu)
{
kvm_arch_vcpu_uninit(vcpu);
free_page((unsigned long)vcpu->run);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
{
return container_of(mn, struct kvm, mmu_notifier);
}
static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long address)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int need_tlb_flush;
/*
* When ->invalidate_page runs, the linux pte has been zapped
* already but the page is still allocated until
* ->invalidate_page returns. So if we increase the sequence
* here the kvm page fault will notice if the spte can't be
* established because the page is going to be freed. If
* instead the kvm page fault establishes the spte before
* ->invalidate_page runs, kvm_unmap_hva will release it
* before returning.
*
* The sequence increase only need to be seen at spin_unlock
* time, and not at spin_lock time.
*
* Increasing the sequence after the spin_unlock would be
* unsafe because the kvm page fault could then establish the
* pte after kvm_unmap_hva returned, without noticing the page
* is going to be freed.
*/
spin_lock(&kvm->mmu_lock);
kvm->mmu_notifier_seq++;
need_tlb_flush = kvm_unmap_hva(kvm, address);
spin_unlock(&kvm->mmu_lock);
/* we've to flush the tlb before the pages can be freed */
if (need_tlb_flush)
kvm_flush_remote_tlbs(kvm);
}
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);
spin_lock(&kvm->mmu_lock);
kvm->mmu_notifier_seq++;
kvm_set_spte_hva(kvm, address, pte);
spin_unlock(&kvm->mmu_lock);
}
static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
unsigned long end)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int need_tlb_flush = 0;
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++;
for (; start < end; start += PAGE_SIZE)
need_tlb_flush |= kvm_unmap_hva(kvm, start);
spin_unlock(&kvm->mmu_lock);
/* we've to flush the tlb before the pages can be freed */
if (need_tlb_flush)
kvm_flush_remote_tlbs(kvm);
}
static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
unsigned long end)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
spin_lock(&kvm->mmu_lock);
/*
* This sequence increase will notify the kvm page fault that
* the page that is going to be mapped in the spte could have
* been freed.
*/
kvm->mmu_notifier_seq++;
/*
* The above sequence increase must be visible before the
* below count decrease but both values are read by the kvm
* page fault under mmu_lock spinlock so we don't need to add
* a smb_wmb() here in between the two.
*/
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,
unsigned long address)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
int young;
spin_lock(&kvm->mmu_lock);
young = kvm_age_hva(kvm, address);
spin_unlock(&kvm->mmu_lock);
if (young)
kvm_flush_remote_tlbs(kvm);
return young;
}
static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
struct mm_struct *mm)
{
struct kvm *kvm = mmu_notifier_to_kvm(mn);
kvm_arch_flush_shadow(kvm);
}
static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
.invalidate_page = kvm_mmu_notifier_invalidate_page,
.invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
.invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
.clear_flush_young = kvm_mmu_notifier_clear_flush_young,
.change_pte = kvm_mmu_notifier_change_pte,
.release = kvm_mmu_notifier_release,
};
#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
static struct kvm *kvm_create_vm(void)
{
int r = 0;
struct kvm *kvm = kvm_arch_create_vm();
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
struct page *page;
#endif
if (IS_ERR(kvm))
goto out;
r = hardware_enable_all();
if (r)
goto out_err_nodisable;
#ifdef CONFIG_HAVE_KVM_IRQCHIP
INIT_HLIST_HEAD(&kvm->mask_notifier_list);
INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
#endif
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
page = alloc_page(GFP_KERNEL | __GFP_ZERO);
if (!page) {
r = -ENOMEM;
goto out_err;
}
kvm->coalesced_mmio_ring =
(struct kvm_coalesced_mmio_ring *)page_address(page);
#endif
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
{
kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
r = mmu_notifier_register(&kvm->mmu_notifier, current->mm);
if (r) {
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
put_page(page);
#endif
goto out_err;
}
}
#endif
kvm->mm = current->mm;
atomic_inc(&kvm->mm->mm_count);
spin_lock_init(&kvm->mmu_lock);
spin_lock_init(&kvm->requests_lock);
kvm_io_bus_init(&kvm->pio_bus);
kvm_eventfd_init(kvm);
mutex_init(&kvm->lock);
mutex_init(&kvm->irq_lock);
kvm_io_bus_init(&kvm->mmio_bus);
init_rwsem(&kvm->slots_lock);
atomic_set(&kvm->users_count, 1);
spin_lock(&kvm_lock);
list_add(&kvm->vm_list, &vm_list);
spin_unlock(&kvm_lock);
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
kvm_coalesced_mmio_init(kvm);
#endif
out:
return kvm;
#if defined(KVM_COALESCED_MMIO_PAGE_OFFSET) || \
(defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER))
out_err:
hardware_disable_all();
#endif
out_err_nodisable:
kfree(kvm);
return ERR_PTR(r);
}
/*
* Free any memory in @free but not in @dont.
*/
static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
struct kvm_memory_slot *dont)
{
int i;
if (!dont || free->rmap != dont->rmap)
vfree(free->rmap);
if (!dont || free->dirty_bitmap != dont->dirty_bitmap)
vfree(free->dirty_bitmap);
for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
if (!dont || free->lpage_info[i] != dont->lpage_info[i]) {
vfree(free->lpage_info[i]);
free->lpage_info[i] = NULL;
}
}
free->npages = 0;
free->dirty_bitmap = NULL;
free->rmap = NULL;
}
void kvm_free_physmem(struct kvm *kvm)
{
int i;
for (i = 0; i < kvm->nmemslots; ++i)
kvm_free_physmem_slot(&kvm->memslots[i], NULL);
}
static void kvm_destroy_vm(struct kvm *kvm)
{
struct mm_struct *mm = kvm->mm;
kvm_arch_sync_events(kvm);
spin_lock(&kvm_lock);
list_del(&kvm->vm_list);
spin_unlock(&kvm_lock);
kvm_free_irq_routing(kvm);
kvm_io_bus_destroy(&kvm->pio_bus);
kvm_io_bus_destroy(&kvm->mmio_bus);
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
if (kvm->coalesced_mmio_ring != NULL)
free_page((unsigned long)kvm->coalesced_mmio_ring);
#endif
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
#else
kvm_arch_flush_shadow(kvm);
#endif
kvm_arch_destroy_vm(kvm);
hardware_disable_all();
mmdrop(mm);
}
void kvm_get_kvm(struct kvm *kvm)
{
atomic_inc(&kvm->users_count);
}
EXPORT_SYMBOL_GPL(kvm_get_kvm);
void kvm_put_kvm(struct kvm *kvm)
{
if (atomic_dec_and_test(&kvm->users_count))
kvm_destroy_vm(kvm);
}
EXPORT_SYMBOL_GPL(kvm_put_kvm);
static int kvm_vm_release(struct inode *inode, struct file *filp)
{
struct kvm *kvm = filp->private_data;
kvm_irqfd_release(kvm);
kvm_put_kvm(kvm);
return 0;
}
/*
* Allocate some memory and give it an address in the guest physical address
* space.
*
* Discontiguous memory is allowed, mostly for framebuffers.
*
* Must be called holding mmap_sem for write.
*/
int __kvm_set_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem,
int user_alloc)
{
int r;
gfn_t base_gfn;
unsigned long npages;
unsigned long i;
struct kvm_memory_slot *memslot;
struct kvm_memory_slot old, new;
r = -EINVAL;
/* General sanity checks */
if (mem->memory_size & (PAGE_SIZE - 1))
goto out;
if (mem->guest_phys_addr & (PAGE_SIZE - 1))
goto out;
if (user_alloc && (mem->userspace_addr & (PAGE_SIZE - 1)))
goto out;
if (mem->slot >= KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS)
goto out;
if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
goto out;
memslot = &kvm->memslots[mem->slot];
base_gfn = mem->guest_phys_addr >> PAGE_SHIFT;
npages = mem->memory_size >> PAGE_SHIFT;
if (!npages)
mem->flags &= ~KVM_MEM_LOG_DIRTY_PAGES;
new = old = *memslot;
new.base_gfn = base_gfn;
new.npages = npages;
new.flags = mem->flags;
/* Disallow changing a memory slot's size. */
r = -EINVAL;
if (npages && old.npages && npages != old.npages)
goto out_free;
/* Check for overlaps */
r = -EEXIST;
for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
struct kvm_memory_slot *s = &kvm->memslots[i];
if (s == memslot || !s->npages)
continue;
if (!((base_gfn + npages <= s->base_gfn) ||
(base_gfn >= s->base_gfn + s->npages)))
goto out_free;
}
/* Free page dirty bitmap if unneeded */
if (!(new.flags & KVM_MEM_LOG_DIRTY_PAGES))
new.dirty_bitmap = NULL;
r = -ENOMEM;
/* Allocate if a slot is being created */
#ifndef CONFIG_S390
if (npages && !new.rmap) {
new.rmap = vmalloc(npages * sizeof(struct page *));
if (!new.rmap)
goto out_free;
memset(new.rmap, 0, npages * sizeof(*new.rmap));
new.user_alloc = user_alloc;
/*
* hva_to_rmmap() serialzies with the mmu_lock and to be
* safe it has to ignore memslots with !user_alloc &&
* !userspace_addr.
*/
if (user_alloc)
new.userspace_addr = mem->userspace_addr;
else
new.userspace_addr = 0;
}
if (!npages)
goto skip_lpage;
for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
unsigned long ugfn;
unsigned long j;
int lpages;
int level = i + 2;
/* Avoid unused variable warning if no large pages */
(void)level;
if (new.lpage_info[i])
continue;
lpages = 1 + (base_gfn + npages - 1) /
KVM_PAGES_PER_HPAGE(level);
lpages -= base_gfn / KVM_PAGES_PER_HPAGE(level);
new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
if (!new.lpage_info[i])
goto out_free;
memset(new.lpage_info[i], 0,
lpages * sizeof(*new.lpage_info[i]));
if (base_gfn % KVM_PAGES_PER_HPAGE(level))
new.lpage_info[i][0].write_count = 1;
if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE(level))
new.lpage_info[i][lpages - 1].write_count = 1;
ugfn = new.userspace_addr >> PAGE_SHIFT;
/*
* If the gfn and userspace address are not aligned wrt each
* other, or if explicitly asked to, disable large page
* support for this slot
*/
if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
!largepages_enabled)
for (j = 0; j < lpages; ++j)
new.lpage_info[i][j].write_count = 1;
}
skip_lpage:
/* Allocate page dirty bitmap if needed */
if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
unsigned dirty_bytes = ALIGN(npages, BITS_PER_LONG) / 8;
new.dirty_bitmap = vmalloc(dirty_bytes);
if (!new.dirty_bitmap)
goto out_free;
memset(new.dirty_bitmap, 0, dirty_bytes);
if (old.npages)
kvm_arch_flush_shadow(kvm);
}
#else /* not defined CONFIG_S390 */
new.user_alloc = user_alloc;
if (user_alloc)
new.userspace_addr = mem->userspace_addr;
#endif /* not defined CONFIG_S390 */
if (!npages)
kvm_arch_flush_shadow(kvm);
spin_lock(&kvm->mmu_lock);
if (mem->slot >= kvm->nmemslots)
kvm->nmemslots = mem->slot + 1;
*memslot = new;
spin_unlock(&kvm->mmu_lock);
r = kvm_arch_set_memory_region(kvm, mem, old, user_alloc);
if (r) {
spin_lock(&kvm->mmu_lock);
*memslot = old;
spin_unlock(&kvm->mmu_lock);
goto out_free;
}
kvm_free_physmem_slot(&old, npages ? &new : NULL);
/* Slot deletion case: we have to update the current slot */
spin_lock(&kvm->mmu_lock);
if (!npages)
*memslot = old;
spin_unlock(&kvm->mmu_lock);
#ifdef CONFIG_DMAR
/* map the pages in iommu page table */
r = kvm_iommu_map_pages(kvm, base_gfn, npages);
if (r)
goto out;
#endif
return 0;
out_free:
kvm_free_physmem_slot(&new, &old);
out:
return r;
}
EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
int kvm_set_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem,
int user_alloc)
{
int r;
down_write(&kvm->slots_lock);
r = __kvm_set_memory_region(kvm, mem, user_alloc);
up_write(&kvm->slots_lock);
return r;
}
EXPORT_SYMBOL_GPL(kvm_set_memory_region);
int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
struct
kvm_userspace_memory_region *mem,
int user_alloc)
{
if (mem->slot >= KVM_MEMORY_SLOTS)
return -EINVAL;
return kvm_set_memory_region(kvm, mem, user_alloc);
}
int kvm_get_dirty_log(struct kvm *kvm,
struct kvm_dirty_log *log, int *is_dirty)
{
struct kvm_memory_slot *memslot;
int r, i;
int n;
unsigned long any = 0;
r = -EINVAL;
if (log->slot >= KVM_MEMORY_SLOTS)
goto out;
memslot = &kvm->memslots[log->slot];
r = -ENOENT;
if (!memslot->dirty_bitmap)
goto out;
n = ALIGN(memslot->npages, BITS_PER_LONG) / 8;
for (i = 0; !any && i < n/sizeof(long); ++i)
any = memslot->dirty_bitmap[i];
r = -EFAULT;
if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
goto out;
if (any)
*is_dirty = 1;
r = 0;
out:
return r;
}
void kvm_disable_largepages(void)
{
largepages_enabled = false;
}
EXPORT_SYMBOL_GPL(kvm_disable_largepages);
int is_error_page(struct page *page)
{
return page == bad_page;
}
EXPORT_SYMBOL_GPL(is_error_page);
int is_error_pfn(pfn_t pfn)
{
return pfn == bad_pfn;
}
EXPORT_SYMBOL_GPL(is_error_pfn);
static inline unsigned long bad_hva(void)
{
return PAGE_OFFSET;
}
int kvm_is_error_hva(unsigned long addr)
{
return addr == bad_hva();
}
EXPORT_SYMBOL_GPL(kvm_is_error_hva);
struct kvm_memory_slot *gfn_to_memslot_unaliased(struct kvm *kvm, gfn_t gfn)
{
int i;
for (i = 0; i < kvm->nmemslots; ++i) {
struct kvm_memory_slot *memslot = &kvm->memslots[i];
if (gfn >= memslot->base_gfn
&& gfn < memslot->base_gfn + memslot->npages)
return memslot;
}
return NULL;
}
EXPORT_SYMBOL_GPL(gfn_to_memslot_unaliased);
struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
{
gfn = unalias_gfn(kvm, gfn);
return gfn_to_memslot_unaliased(kvm, gfn);
}
int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
{
int i;
gfn = unalias_gfn(kvm, gfn);
for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
struct kvm_memory_slot *memslot = &kvm->memslots[i];
if (gfn >= memslot->base_gfn
&& gfn < memslot->base_gfn + memslot->npages)
return 1;
}
return 0;
}
EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
{
struct kvm_memory_slot *slot;
gfn = unalias_gfn(kvm, gfn);
slot = gfn_to_memslot_unaliased(kvm, gfn);
if (!slot)
return bad_hva();
return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
}
EXPORT_SYMBOL_GPL(gfn_to_hva);
pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
{
struct page *page[1];
unsigned long addr;
int npages;
pfn_t pfn;
might_sleep();
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr)) {
get_page(bad_page);
return page_to_pfn(bad_page);
}
npages = get_user_pages_fast(addr, 1, 1, page);
if (unlikely(npages != 1)) {
struct vm_area_struct *vma;
down_read(¤t->mm->mmap_sem);
vma = find_vma(current->mm, addr);
if (vma == NULL || addr < vma->vm_start ||
!(vma->vm_flags & VM_PFNMAP)) {
up_read(¤t->mm->mmap_sem);
get_page(bad_page);
return page_to_pfn(bad_page);
}
pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
up_read(¤t->mm->mmap_sem);
BUG_ON(!kvm_is_mmio_pfn(pfn));
} else
pfn = page_to_pfn(page[0]);
return pfn;
}
EXPORT_SYMBOL_GPL(gfn_to_pfn);
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
{
pfn_t pfn;
pfn = gfn_to_pfn(kvm, gfn);
if (!kvm_is_mmio_pfn(pfn))
return pfn_to_page(pfn);
WARN_ON(kvm_is_mmio_pfn(pfn));
get_page(bad_page);
return bad_page;
}
EXPORT_SYMBOL_GPL(gfn_to_page);
void kvm_release_page_clean(struct page *page)
{
kvm_release_pfn_clean(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_clean);
void kvm_release_pfn_clean(pfn_t pfn)
{
if (!kvm_is_mmio_pfn(pfn))
put_page(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
void kvm_release_page_dirty(struct page *page)
{
kvm_release_pfn_dirty(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
void kvm_release_pfn_dirty(pfn_t pfn)
{
kvm_set_pfn_dirty(pfn);
kvm_release_pfn_clean(pfn);
}
EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
void kvm_set_page_dirty(struct page *page)
{
kvm_set_pfn_dirty(page_to_pfn(page));
}
EXPORT_SYMBOL_GPL(kvm_set_page_dirty);
void kvm_set_pfn_dirty(pfn_t pfn)
{
if (!kvm_is_mmio_pfn(pfn)) {
struct page *page = pfn_to_page(pfn);
if (!PageReserved(page))
SetPageDirty(page);
}
}
EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
void kvm_set_pfn_accessed(pfn_t pfn)
{
if (!kvm_is_mmio_pfn(pfn))
mark_page_accessed(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
void kvm_get_pfn(pfn_t pfn)
{
if (!kvm_is_mmio_pfn(pfn))
get_page(pfn_to_page(pfn));
}
EXPORT_SYMBOL_GPL(kvm_get_pfn);
static int next_segment(unsigned long len, int offset)
{
if (len > PAGE_SIZE - offset)
return PAGE_SIZE - offset;
else
return len;
}
int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
int len)
{
int r;
unsigned long addr;
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
r = copy_from_user(data, (void __user *)addr + offset, len);
if (r)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL_GPL(kvm_read_guest_page);
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);
int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
unsigned long len)
{
int r;
unsigned long addr;
gfn_t gfn = gpa >> PAGE_SHIFT;
int offset = offset_in_page(gpa);
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
pagefault_disable();
r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
pagefault_enable();
if (r)
return -EFAULT;
return 0;
}
EXPORT_SYMBOL(kvm_read_guest_atomic);
int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data,
int offset, int len)
{
int r;
unsigned long addr;
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return -EFAULT;
r = copy_to_user((void __user *)addr + offset, data, len);
if (r)
return -EFAULT;
mark_page_dirty(kvm, gfn);
return 0;
}
EXPORT_SYMBOL_GPL(kvm_write_guest_page);
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;
}
int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len)
{
return kvm_write_guest_page(kvm, gfn, empty_zero_page, offset, len);
}
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;
while ((seg = next_segment(len, offset)) != 0) {
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);
void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
{
struct kvm_memory_slot *memslot;
gfn = unalias_gfn(kvm, gfn);
memslot = gfn_to_memslot_unaliased(kvm, gfn);
if (memslot && memslot->dirty_bitmap) {
unsigned long rel_gfn = gfn - memslot->base_gfn;
/* avoid RMW */
if (!generic_test_le_bit(rel_gfn, memslot->dirty_bitmap))
generic___set_le_bit(rel_gfn, memslot->dirty_bitmap);
}
}
/*
* The vCPU has executed a HLT instruction with in-kernel mode enabled.
*/
void kvm_vcpu_block(struct kvm_vcpu *vcpu)
{
DEFINE_WAIT(wait);
for (;;) {
prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
if (kvm_arch_vcpu_runnable(vcpu)) {
set_bit(KVM_REQ_UNHALT, &vcpu->requests);
break;
}
if (kvm_cpu_has_pending_timer(vcpu))
break;
if (signal_pending(current))
break;
schedule();
}
finish_wait(&vcpu->wq, &wait);
}
void kvm_resched(struct kvm_vcpu *vcpu)
{
if (!need_resched())
return;
cond_resched();
}
EXPORT_SYMBOL_GPL(kvm_resched);
void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu)
{
ktime_t expires;
DEFINE_WAIT(wait);
prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
/* Sleep for 100 us, and hope lock-holder got scheduled */
expires = ktime_add_ns(ktime_get(), 100000UL);
schedule_hrtimeout(&expires, HRTIMER_MODE_ABS);
finish_wait(&vcpu->wq, &wait);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
static int kvm_vcpu_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct kvm_vcpu *vcpu = vma->vm_file->private_data;
struct page *page;
if (vmf->pgoff == 0)
page = virt_to_page(vcpu->run);
#ifdef CONFIG_X86
else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
page = virt_to_page(vcpu->arch.pio_data);
#endif
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
#endif
else
return VM_FAULT_SIGBUS;
get_page(page);
vmf->page = page;
return 0;
}
static const struct vm_operations_struct kvm_vcpu_vm_ops = {
.fault = kvm_vcpu_fault,
};
static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
{
vma->vm_ops = &kvm_vcpu_vm_ops;
return 0;
}
static int kvm_vcpu_release(struct inode *inode, struct file *filp)
{
struct kvm_vcpu *vcpu = filp->private_data;
kvm_put_kvm(vcpu->kvm);
return 0;
}
static struct file_operations kvm_vcpu_fops = {
.release = kvm_vcpu_release,
.unlocked_ioctl = kvm_vcpu_ioctl,
.compat_ioctl = kvm_vcpu_ioctl,
.mmap = kvm_vcpu_mmap,
};
/*
* Allocates an inode for the vcpu.
*/
static int create_vcpu_fd(struct kvm_vcpu *vcpu)
{
return anon_inode_getfd("kvm-vcpu", &kvm_vcpu_fops, vcpu, O_RDWR);
}
/*
* Creates some virtual cpus. Good luck creating more than one.
*/
static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
{
int r;
struct kvm_vcpu *vcpu, *v;
vcpu = kvm_arch_vcpu_create(kvm, id);
if (IS_ERR(vcpu))
return PTR_ERR(vcpu);
preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
r = kvm_arch_vcpu_setup(vcpu);
if (r)
return r;
mutex_lock(&kvm->lock);
if (atomic_read(&kvm->online_vcpus) == KVM_MAX_VCPUS) {
r = -EINVAL;
goto vcpu_destroy;
}
kvm_for_each_vcpu(r, v, kvm)
if (v->vcpu_id == id) {
r = -EEXIST;
goto vcpu_destroy;
}
BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]);
/* Now it's all set up, let userspace reach it */
kvm_get_kvm(kvm);
r = create_vcpu_fd(vcpu);
if (r < 0) {
kvm_put_kvm(kvm);
goto vcpu_destroy;
}
kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
smp_wmb();
atomic_inc(&kvm->online_vcpus);
#ifdef CONFIG_KVM_APIC_ARCHITECTURE
if (kvm->bsp_vcpu_id == id)
kvm->bsp_vcpu = vcpu;
#endif
mutex_unlock(&kvm->lock);
return r;
vcpu_destroy:
mutex_unlock(&kvm->lock);
kvm_arch_vcpu_destroy(vcpu);
return r;
}
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;
}
static long kvm_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
int r;
struct kvm_fpu *fpu = NULL;
struct kvm_sregs *kvm_sregs = NULL;
if (vcpu->kvm->mm != current->mm)
return -EIO;
switch (ioctl) {
case KVM_RUN:
r = -EINVAL;
if (arg)
goto out;
r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run);
break;
case KVM_GET_REGS: {
struct kvm_regs *kvm_regs;
r = -ENOMEM;
kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
if (!kvm_regs)
goto out;
r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
if (r)
goto out_free1;
r = -EFAULT;
if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
goto out_free1;
r = 0;
out_free1:
kfree(kvm_regs);
break;
}
case KVM_SET_REGS: {
struct kvm_regs *kvm_regs;
r = -ENOMEM;
kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL);
if (!kvm_regs)
goto out;
r = -EFAULT;
if (copy_from_user(kvm_regs, argp, sizeof(struct kvm_regs)))
goto out_free2;
r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
if (r)
goto out_free2;
r = 0;
out_free2:
kfree(kvm_regs);
break;
}
case KVM_GET_SREGS: {
kvm_sregs = kzalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
r = -ENOMEM;
if (!kvm_sregs)
goto out;
r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
if (r)
goto out;
r = -EFAULT;
if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
goto out;
r = 0;
break;
}
case KVM_SET_SREGS: {
kvm_sregs = kmalloc(sizeof(struct kvm_sregs), GFP_KERNEL);
r = -ENOMEM;
if (!kvm_sregs)
goto out;
r = -EFAULT;
if (copy_from_user(kvm_sregs, argp, sizeof(struct kvm_sregs)))
goto out;
r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
if (r)
goto out;
r = 0;
break;
}
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;
if (copy_to_user(argp, &mp_state, sizeof mp_state))
goto out;
r = 0;
break;
}
case KVM_SET_MP_STATE: {
struct kvm_mp_state mp_state;
r = -EFAULT;
if (copy_from_user(&mp_state, argp, sizeof mp_state))
goto out;
r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
if (r)
goto out;
r = 0;
break;
}
case KVM_TRANSLATE: {
struct kvm_translation tr;
r = -EFAULT;
if (copy_from_user(&tr, argp, sizeof tr))
goto out;
r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
if (r)
goto out;
r = -EFAULT;
if (copy_to_user(argp, &tr, sizeof tr))
goto out;
r = 0;
break;
}
case KVM_SET_GUEST_DEBUG: {
struct kvm_guest_debug dbg;
r = -EFAULT;
if (copy_from_user(&dbg, argp, sizeof dbg))
goto out;
r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
if (r)
goto out;
r = 0;
break;
}
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,
sizeof kvm_sigmask))
goto out;
r = -EINVAL;
if (kvm_sigmask.len != sizeof sigset)
goto out;
r = -EFAULT;
if (copy_from_user(&sigset, sigmask_arg->sigset,
sizeof sigset))
goto out;
p = &sigset;
}
r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
break;
}
case KVM_GET_FPU: {
fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
r = -ENOMEM;
if (!fpu)
goto out;
r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
if (r)
goto out;
r = -EFAULT;
if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
goto out;
r = 0;
break;
}
case KVM_SET_FPU: {
fpu = kmalloc(sizeof(struct kvm_fpu), GFP_KERNEL);
r = -ENOMEM;
if (!fpu)
goto out;
r = -EFAULT;
if (copy_from_user(fpu, argp, sizeof(struct kvm_fpu)))
goto out;
r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
if (r)
goto out;
r = 0;
break;
}
default:
r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
}
out:
kfree(fpu);
kfree(kvm_sregs);
return r;
}
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;
int r;
if (kvm->mm != current->mm)
return -EIO;
switch (ioctl) {
case KVM_CREATE_VCPU:
r = kvm_vm_ioctl_create_vcpu(kvm, arg);
if (r < 0)
goto out;
break;
case KVM_SET_USER_MEMORY_REGION: {
struct kvm_userspace_memory_region kvm_userspace_mem;
r = -EFAULT;
if (copy_from_user(&kvm_userspace_mem, argp,
sizeof kvm_userspace_mem))
goto out;
r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem, 1);
if (r)
goto out;
break;
}
case KVM_GET_DIRTY_LOG: {
struct kvm_dirty_log log;
r = -EFAULT;
if (copy_from_user(&log, argp, sizeof log))
goto out;
r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
if (r)
goto out;
break;
}
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
case KVM_REGISTER_COALESCED_MMIO: {
struct kvm_coalesced_mmio_zone zone;
r = -EFAULT;
if (copy_from_user(&zone, argp, sizeof zone))
goto out;
r = -ENXIO;
r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
if (r)
goto out;
r = 0;
break;
}
case KVM_UNREGISTER_COALESCED_MMIO: {
struct kvm_coalesced_mmio_zone zone;
r = -EFAULT;
if (copy_from_user(&zone, argp, sizeof zone))
goto out;
r = -ENXIO;
r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
if (r)
goto out;
r = 0;
break;
}
#endif
case KVM_IRQFD: {
struct kvm_irqfd data;
r = -EFAULT;
if (copy_from_user(&data, argp, sizeof data))
goto out;
r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
break;
}
case KVM_IOEVENTFD: {
struct kvm_ioeventfd data;
r = -EFAULT;
if (copy_from_user(&data, argp, sizeof data))
goto out;
r = kvm_ioeventfd(kvm, &data);
break;
}
#ifdef CONFIG_KVM_APIC_ARCHITECTURE
case KVM_SET_BOOT_CPU_ID:
r = 0;
mutex_lock(&kvm->lock);
if (atomic_read(&kvm->online_vcpus) != 0)
r = -EBUSY;
else
kvm->bsp_vcpu_id = arg;
mutex_unlock(&kvm->lock);
break;
#endif
default:
r = kvm_arch_vm_ioctl(filp, ioctl, arg);
if (r == -ENOTTY)
r = kvm_vm_ioctl_assigned_device(kvm, ioctl, arg);
}
out:
return r;
}
#ifdef CONFIG_COMPAT
struct compat_kvm_dirty_log {
__u32 slot;
__u32 padding1;
union {
compat_uptr_t dirty_bitmap; /* one bit per page */
__u64 padding2;
};
};
static long kvm_vm_compat_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm *kvm = filp->private_data;
int r;
if (kvm->mm != current->mm)
return -EIO;
switch (ioctl) {
case KVM_GET_DIRTY_LOG: {
struct compat_kvm_dirty_log compat_log;
struct kvm_dirty_log log;
r = -EFAULT;
if (copy_from_user(&compat_log, (void __user *)arg,
sizeof(compat_log)))
goto out;
log.slot = compat_log.slot;
log.padding1 = compat_log.padding1;
log.padding2 = compat_log.padding2;
log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
if (r)
goto out;
break;
}
default:
r = kvm_vm_ioctl(filp, ioctl, arg);
}
out:
return r;
}
#endif
static int kvm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct page *page[1];
unsigned long addr;
int npages;
gfn_t gfn = vmf->pgoff;
struct kvm *kvm = vma->vm_file->private_data;
addr = gfn_to_hva(kvm, gfn);
if (kvm_is_error_hva(addr))
return VM_FAULT_SIGBUS;
npages = get_user_pages(current, current->mm, addr, 1, 1, 0, page,
NULL);
if (unlikely(npages != 1))
return VM_FAULT_SIGBUS;
vmf->page = page[0];
return 0;
}
static const struct vm_operations_struct kvm_vm_vm_ops = {
.fault = kvm_vm_fault,
};
static int kvm_vm_mmap(struct file *file, struct vm_area_struct *vma)
{
vma->vm_ops = &kvm_vm_vm_ops;
return 0;
}
static struct file_operations kvm_vm_fops = {
.release = kvm_vm_release,
.unlocked_ioctl = kvm_vm_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = kvm_vm_compat_ioctl,
#endif
.mmap = kvm_vm_mmap,
};
static int kvm_dev_ioctl_create_vm(void)
{
int fd;
struct kvm *kvm;
kvm = kvm_create_vm();
if (IS_ERR(kvm))
return PTR_ERR(kvm);
fd = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
if (fd < 0)
kvm_put_kvm(kvm);
return fd;
}
static long kvm_dev_ioctl_check_extension_generic(long arg)
{
switch (arg) {
case KVM_CAP_USER_MEMORY:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
#ifdef CONFIG_KVM_APIC_ARCHITECTURE
case KVM_CAP_SET_BOOT_CPU_ID:
#endif
case KVM_CAP_INTERNAL_ERROR_DATA:
return 1;
#ifdef CONFIG_HAVE_KVM_IRQCHIP
case KVM_CAP_IRQ_ROUTING:
return KVM_MAX_IRQ_ROUTES;
#endif
default:
break;
}
return kvm_dev_ioctl_check_extension(arg);
}
static long kvm_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
long r = -EINVAL;
switch (ioctl) {
case KVM_GET_API_VERSION:
r = -EINVAL;
if (arg)
goto out;
r = KVM_API_VERSION;
break;
case KVM_CREATE_VM:
r = -EINVAL;
if (arg)
goto out;
r = kvm_dev_ioctl_create_vm();
break;
case KVM_CHECK_EXTENSION:
r = kvm_dev_ioctl_check_extension_generic(arg);
break;
case KVM_GET_VCPU_MMAP_SIZE:
r = -EINVAL;
if (arg)
goto out;
r = PAGE_SIZE; /* struct kvm_run */
#ifdef CONFIG_X86
r += PAGE_SIZE; /* pio data page */
#endif
#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET
r += PAGE_SIZE; /* coalesced mmio ring page */
#endif
break;
case KVM_TRACE_ENABLE:
case KVM_TRACE_PAUSE:
case KVM_TRACE_DISABLE:
r = -EOPNOTSUPP;
break;
default:
return kvm_arch_dev_ioctl(filp, ioctl, arg);
}
out:
return r;
}
static struct file_operations kvm_chardev_ops = {
.unlocked_ioctl = kvm_dev_ioctl,
.compat_ioctl = kvm_dev_ioctl,
};
static struct miscdevice kvm_dev = {
KVM_MINOR,
"kvm",
&kvm_chardev_ops,
};
static void hardware_enable(void *junk)
{
int cpu = raw_smp_processor_id();
int r;
if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
return;
cpumask_set_cpu(cpu, cpus_hardware_enabled);
r = kvm_arch_hardware_enable(NULL);
if (r) {
cpumask_clear_cpu(cpu, cpus_hardware_enabled);
atomic_inc(&hardware_enable_failed);
printk(KERN_INFO "kvm: enabling virtualization on "
"CPU%d failed\n", cpu);
}
}
static void hardware_disable(void *junk)
{
int cpu = raw_smp_processor_id();
if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
return;
cpumask_clear_cpu(cpu, cpus_hardware_enabled);
kvm_arch_hardware_disable(NULL);
}
static void hardware_disable_all_nolock(void)
{
BUG_ON(!kvm_usage_count);
kvm_usage_count--;
if (!kvm_usage_count)
on_each_cpu(hardware_disable, NULL, 1);
}
static void hardware_disable_all(void)
{
spin_lock(&kvm_lock);
hardware_disable_all_nolock();
spin_unlock(&kvm_lock);
}
static int hardware_enable_all(void)
{
int r = 0;
spin_lock(&kvm_lock);
kvm_usage_count++;
if (kvm_usage_count == 1) {
atomic_set(&hardware_enable_failed, 0);
on_each_cpu(hardware_enable, NULL, 1);
if (atomic_read(&hardware_enable_failed)) {
hardware_disable_all_nolock();
r = -EBUSY;
}
}
spin_unlock(&kvm_lock);
return r;
}
static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
void *v)
{
int cpu = (long)v;
if (!kvm_usage_count)
return NOTIFY_OK;
val &= ~CPU_TASKS_FROZEN;
switch (val) {
case CPU_DYING:
printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
cpu);
hardware_disable(NULL);
break;
case CPU_UP_CANCELED:
printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
cpu);
smp_call_function_single(cpu, hardware_disable, NULL, 1);
break;
case CPU_ONLINE:
printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
cpu);
smp_call_function_single(cpu, hardware_enable, NULL, 1);
break;
}
return NOTIFY_OK;
}
asmlinkage void kvm_handle_fault_on_reboot(void)
{
if (kvm_rebooting)
/* spin while reset goes on */
while (true)
;
/* Fault while not rebooting. We want the trace. */
BUG();
}
EXPORT_SYMBOL_GPL(kvm_handle_fault_on_reboot);
static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
void *v)
{
/*
* 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.
*/
printk(KERN_INFO "kvm: exiting hardware virtualization\n");
kvm_rebooting = true;
on_each_cpu(hardware_disable, NULL, 1);
return NOTIFY_OK;
}
static struct notifier_block kvm_reboot_notifier = {
.notifier_call = kvm_reboot,
.priority = 0,
};
void kvm_io_bus_init(struct kvm_io_bus *bus)
{
memset(bus, 0, sizeof(*bus));
}
void kvm_io_bus_destroy(struct kvm_io_bus *bus)
{
int i;
for (i = 0; i < bus->dev_count; i++) {
struct kvm_io_device *pos = bus->devs[i];
kvm_iodevice_destructor(pos);
}
}
/* kvm_io_bus_write - called under kvm->slots_lock */
int kvm_io_bus_write(struct kvm_io_bus *bus, gpa_t addr,
int len, const void *val)
{
int i;
for (i = 0; i < bus->dev_count; i++)
if (!kvm_iodevice_write(bus->devs[i], addr, len, val))
return 0;
return -EOPNOTSUPP;
}
/* kvm_io_bus_read - called under kvm->slots_lock */
int kvm_io_bus_read(struct kvm_io_bus *bus, gpa_t addr, int len, void *val)
{
int i;
for (i = 0; i < bus->dev_count; i++)
if (!kvm_iodevice_read(bus->devs[i], addr, len, val))
return 0;
return -EOPNOTSUPP;
}
int kvm_io_bus_register_dev(struct kvm *kvm, struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
int ret;
down_write(&kvm->slots_lock);
ret = __kvm_io_bus_register_dev(bus, dev);
up_write(&kvm->slots_lock);
return ret;
}
/* An unlocked version. Caller must have write lock on slots_lock. */
int __kvm_io_bus_register_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
if (bus->dev_count > NR_IOBUS_DEVS-1)
return -ENOSPC;
bus->devs[bus->dev_count++] = dev;
return 0;
}
void kvm_io_bus_unregister_dev(struct kvm *kvm,
struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
down_write(&kvm->slots_lock);
__kvm_io_bus_unregister_dev(bus, dev);
up_write(&kvm->slots_lock);
}
/* An unlocked version. Caller must have write lock on slots_lock. */
void __kvm_io_bus_unregister_dev(struct kvm_io_bus *bus,
struct kvm_io_device *dev)
{
int i;
for (i = 0; i < bus->dev_count; i++)
if (bus->devs[i] == dev) {
bus->devs[i] = bus->devs[--bus->dev_count];
break;
}
}
static struct notifier_block kvm_cpu_notifier = {
.notifier_call = kvm_cpu_hotplug,
.priority = 20, /* must be > scheduler priority */
};
static int vm_stat_get(void *_offset, u64 *val)
{
unsigned offset = (long)_offset;
struct kvm *kvm;
*val = 0;
spin_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list)
*val += *(u32 *)((void *)kvm + offset);
spin_unlock(&kvm_lock);
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, NULL, "%llu\n");
static int vcpu_stat_get(void *_offset, u64 *val)
{
unsigned offset = (long)_offset;
struct kvm *kvm;
struct kvm_vcpu *vcpu;
int i;
*val = 0;
spin_lock(&kvm_lock);
list_for_each_entry(kvm, &vm_list, vm_list)
kvm_for_each_vcpu(i, vcpu, kvm)
*val += *(u32 *)((void *)vcpu + offset);
spin_unlock(&kvm_lock);
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, NULL, "%llu\n");
static const struct file_operations *stat_fops[] = {
[KVM_STAT_VCPU] = &vcpu_stat_fops,
[KVM_STAT_VM] = &vm_stat_fops,
};
static void kvm_init_debug(void)
{
struct kvm_stats_debugfs_item *p;
kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
for (p = debugfs_entries; p->name; ++p)
p->dentry = debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
(void *)(long)p->offset,
stat_fops[p->kind]);
}
static void kvm_exit_debug(void)
{
struct kvm_stats_debugfs_item *p;
for (p = debugfs_entries; p->name; ++p)
debugfs_remove(p->dentry);
debugfs_remove(kvm_debugfs_dir);
}
static int kvm_suspend(struct sys_device *dev, pm_message_t state)
{
if (kvm_usage_count)
hardware_disable(NULL);
return 0;
}
static int kvm_resume(struct sys_device *dev)
{
if (kvm_usage_count)
hardware_enable(NULL);
return 0;
}
static struct sysdev_class kvm_sysdev_class = {
.name = "kvm",
.suspend = kvm_suspend,
.resume = kvm_resume,
};
static struct sys_device kvm_sysdev = {
.id = 0,
.cls = &kvm_sysdev_class,
};
struct page *bad_page;
pfn_t bad_pfn;
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);
kvm_arch_vcpu_load(vcpu, cpu);
}
static void kvm_sched_out(struct preempt_notifier *pn,
struct task_struct *next)
{
struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
kvm_arch_vcpu_put(vcpu);
}
int kvm_init(void *opaque, unsigned int vcpu_size,
struct module *module)
{
int r;
int cpu;
r = kvm_arch_init(opaque);
if (r)
goto out_fail;
bad_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
if (bad_page == NULL) {
r = -ENOMEM;
goto out;
}
bad_pfn = page_to_pfn(bad_page);
if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
r = -ENOMEM;
goto out_free_0;
}
r = kvm_arch_hardware_setup();
if (r < 0)
goto out_free_0a;
for_each_online_cpu(cpu) {
smp_call_function_single(cpu,
kvm_arch_check_processor_compat,
&r, 1);
if (r < 0)
goto out_free_1;
}
r = register_cpu_notifier(&kvm_cpu_notifier);
if (r)
goto out_free_2;
register_reboot_notifier(&kvm_reboot_notifier);
r = sysdev_class_register(&kvm_sysdev_class);
if (r)
goto out_free_3;
r = sysdev_register(&kvm_sysdev);
if (r)
goto out_free_4;
/* A kmem cache lets us meet the alignment requirements of fx_save. */
kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size,
__alignof__(struct kvm_vcpu),
0, NULL);
if (!kvm_vcpu_cache) {
r = -ENOMEM;
goto out_free_5;
}
kvm_chardev_ops.owner = module;
kvm_vm_fops.owner = module;
kvm_vcpu_fops.owner = module;
r = misc_register(&kvm_dev);
if (r) {
printk(KERN_ERR "kvm: misc device register failed\n");
goto out_free;
}
kvm_preempt_ops.sched_in = kvm_sched_in;
kvm_preempt_ops.sched_out = kvm_sched_out;
kvm_init_debug();
return 0;
out_free:
kmem_cache_destroy(kvm_vcpu_cache);
out_free_5:
sysdev_unregister(&kvm_sysdev);
out_free_4:
sysdev_class_unregister(&kvm_sysdev_class);
out_free_3:
unregister_reboot_notifier(&kvm_reboot_notifier);
unregister_cpu_notifier(&kvm_cpu_notifier);
out_free_2:
out_free_1:
kvm_arch_hardware_unsetup();
out_free_0a:
free_cpumask_var(cpus_hardware_enabled);
out_free_0:
__free_page(bad_page);
out:
kvm_arch_exit();
out_fail:
return r;
}
EXPORT_SYMBOL_GPL(kvm_init);
void kvm_exit(void)
{
tracepoint_synchronize_unregister();
kvm_exit_debug();
misc_deregister(&kvm_dev);
kmem_cache_destroy(kvm_vcpu_cache);
sysdev_unregister(&kvm_sysdev);
sysdev_class_unregister(&kvm_sysdev_class);
unregister_reboot_notifier(&kvm_reboot_notifier);
unregister_cpu_notifier(&kvm_cpu_notifier);
on_each_cpu(hardware_disable, NULL, 1);
kvm_arch_hardware_unsetup();
kvm_arch_exit();
free_cpumask_var(cpus_hardware_enabled);
__free_page(bad_page);
}
EXPORT_SYMBOL_GPL(kvm_exit);